A Literature Review surrounding the diagnosis and management of Spondylolysis and Spondylolisthesis in athletes.

Spondylolysis is a lesion caused by stress fractures at the pars interarticularis, while a spondylolisthesis is the anterior translation of a spondylolytic section, usually in the lumbar spine. Progressive in nature, both conditions can lead to short and long term problems if untreated. Affected individuals often ignore the warning signs until the condition has progressed to an advanced stage, making management and resolution challenging and time consuming. I will discuss the epidemiology and progression of pars lesions, how they specifically affect an athletic population and how the conditions are diagnosed and managed focusing on current and future concepts.

 

Lower back pain is a common complaint and affects 85-90% of the general population at some point during their lives and between 2-5% of people per year (Trainor & Wiesel, 2002). Although limited evidence exists, some age matched studies suggest a higher prevalence of back pain among athletes (Kujala, Taimela, Erkintalo, Salminen, & Kaprio, 1996). Beaty, (1999, cited by Trainor & Wiesel, 2002) suggests that 6-13% of all back injuries are sport related while d'Hemecourt, Gerbino & Micheli, (2000) reports 10-15% of adolescent athletes experience lower back pain during sport, indicating that sports related lower back pain is relatively common.

 

Spondylolysis affects approximately 6% of the general population (Fredrickson, Baker, McHolick, Yuan & Lubicky, 1984). This figure has been formulated through plain radiographic evidence however with better imaging techniques; a high incidence of spondylolysis has been suggested (Kalichman, Kim, Li, Guermazi, Berkin & Hunter, 2009 and Teplick, Laffey, Berman & Haskin, 1986). The majority of spondylolytic defects are reported to be asymptomatic with about 25% of the symptomatic cases presenting with an associated spondylolisthesis (Fredrickson et al, 1984).

 

Rossi & Dragoni, (2001), report a higher radiographic prevalence of spondylolysis (13.9%) and spondylolisthesis (6.5%) in an athletic population with lower back pain (4243), in contrary to Soler & Calderón, (2000), who report, through similar methods, a marginally higher spondylolysis (8.1%) and spondylolisthesis (2.5%) prevalence in a comparable athletic population without back pain (3152). The conclusions which can be drawn from both studies confirm that certain sport, artistic gymnastics (17%), throwing field events (17-26%) and wrestling (25%), have a significantly higher percentage of spondylolytic and spondylolisthetic lesions than other sports events. Symptomatic back pain seems to be an indicator of increased likelihood of a pars defect, with a higher prevalence in some sports being attributed to a hyperextension movement with axial loading. Both studies compared the prevalence of pars defects in male and female subjects. Rossi & Dragoni (2001) found a significantly greater ratio of men (4.5:1) with a spondylolysis compared to Soler & Calderón, (2000), who found a 1:1 ratio between men and women. The latter study had a significantly higher percentage of females with spondylolisthetic lesions which according to the literature is expected (Seitsalo, Osterman & Hyvarinen, 1991, cited by Soler & Calderón, 2000). Future research may further investigate the effects of specific female overtraining syndromes, like the female triad and how these relate spinal stress fractures. 

 

Rossi & Dragoni (2001) and Soler & Calderón, (2000), found L₅ the most commonly affected level (81% and 84% respectively). The incidence decreases through each of the levels, with almost no involvement at L₁ and S₁. Similarly most of the pars defects were reported to involve only one segment (95% and 96%) with the remaining lesions affecting two or more different segments. The majority of radiographically diagnosed spondylolytic defects have been reported to be bilateral (86% and 78%), indicating a stress fracture at the right and left pars interarticularis on a single segment (Rossi & Dragoni, 2001 and Soler & Calderón, 2000). This value may have a significant meaning when determining best treatment practice, as unilateral stress fractures tend to have a much higher union rate especially when early diagnosis and better imaging techniques are used.

 

Adolescent athletes with back pain have a significantly higher percentage of spondylolytic lesions (47%) when compared to an adult population (5%) (Micheli & Wood, 1995). This suggests that lower back pain could be due to a pars defect especially in adolescent athletes who participate in repetitive loading sports. There may also be a connection between spondylolytic lesions and the adolescent growth phase. Some literature suggests that children who participate in sport are at a higher risk of spondylolisthetic progression (Muschik, Hahnel, Robinson, Perka & Muschik, 1996). There seems to be no good evidence limiting sports participation in an adolescent population due to pars defects.

 

Early diagnosis is vital in effective management of spondylolytic and spondylolisthetic disorders. Contributing factors include increased lumbar lordosis and associated factors like, abdominal weakness and shortening in the iliopsoas, hamstrings and thoracolumbar fascia (d'Hemecourt et al., 2000). Participation in sports activities which involve hyperextension of the lumbar spine, repetitive spinal movements, a variety of high velocity spinal movements and axial loading (Gregory, Batt & Kerslake, 2005) are the main causes of pars defects. Pain is normally confined to the lumbar spine with occasional pain in the gluteal region and posterior thigh, often associated with muscle shortening as opposed to radiculopathy (McCleary & Congeni, 2007). Some individuals demonstrate an increased lumbar lordosis due to a larger sacro-horizontal angle which may predispose them to spondylolytic defects especially if involved in specific loading sports (Sward, Hellstrom, Jacobsson, & Peterson, 1989). In a higher grade spondylolisthetic defect, a step-off may be palpated and can be associated with point tenderness over the effected spinous process which is also evident in some cases of spondylolysis (Bono, 2004). Jackson, Wiltse & Cirincoine, (1976 cited by Bono, 2004) described the single leg hyperextension test which involves the individual standing on one leg and hyperextending the lumbar spine. The test is positive for a pars lesion if pain is reproduced on the standing leg side. No literature has reported on the reliability or validity of this test.

 

Plain radiographs are traditionally requested for individuals presenting with lower back pain that are involved in certain higher risk sports and a spondylolysis is suspected. The normal views consist of antero-posterior, lateral and oblique views; however a cone-down lateral radiograph produces a clearer image of the posterior bone structure at L₅/S₁ than a normal lateral view (Pennell, Maurer & Bonakdarpour, 1985). The oblique radiographs can be beneficial in detecting a defect in that plane but left and right images should be taken. According to the Meyerding (1932) scale, spondylolisthesis is graded on a lateral radiograph, with grade I indicating a slip <25%; grade II, 25-50%; grade III, 50-75%; and grade IV, 75-100% however grade IV spondylolisthesis rarely occur. Some controversy exists regarding the usefulness of plain radiographs. Kalichman, et al., (2009) found a significantly higher proportion (11.5%) of spondylolytic defects in an adult population with lower back pain, detected with computed tomography (CT) compared to plain radiographs. Similarly (Saifuddin, White, Tucker & Taylor, 1997) compared CT to oblique radiographs in 34 patients with 69 defects. Only 32% of the defects were detected on the radiographs, suggesting poor sensitivity especially in early stage spondylolysis compared to CT. Radiographic imaging may still be useful in identifying advanced defects. They are significantly cheaper than other imaging techniques and accessible, however radiographs should not be considered as a definitive diagnosis of spondylolysis.  

 

When plain radiographs reveal negative findings in patients with persistent symptoms a bone scan, CT, single-photon-emission computed tomography (SPECT) or magnetic resonance imaging (MRI) can be used to achieve a more reliable diagnosis. A bone scan or scintigraphy is an investigation method which detects areas of bone turnover or stress reaction, which can represent an impending stress fracture. Jackson, Wiltse, Dingeman & Hayes, (1981) investigated 37 young athletes using plain radiographs and bone scans. The results indicated that 19% of the young athletes showed signs of a stress reaction with no visible pars defect. Interestingly all seven stress reactions were unilateral involving only one segment. This may indicate that if a stress reaction is identified and managed early, progression to the more common bilateral spondylolytic lesion may be prevented.

 

Current literature suggests that SPECT is the most sensitive test to detect lesions at the pars interarticularis (Harvey, Richenberg, Saifuddin & Wolman, 1998). Like bone scans, SPECT has been shown to reveal pars lesions before the development of radiographic changes but has also been shown to be a more sensitive investigation than bone scans. Bellah, Summerville, Treves & Micheli, (1991) found radiotracer uptake using SPECT in 44% of an adolescent athletic population. Only 32 of those 71 subjects showed radiotracer uptake when using a bone scan. This allows for an earlier diagnosis of bone stress reaction. A useful consequence of SPECT is that it shows up active and inactive spondylolysis. An active spondylolysis indicates higher rates of bone turn over which Sys, Michielsen, Bracke, Martens & Verstreken, (2001) suggest has a much better healing capacity but could also explain painful symptoms associated with the healing process. Limitations with SPECT are high exposure to radiation and it is time consuming. Harvey et al., (1998) also remark on SPECT’s lack of sensitivity to differentiate between pathology.

 

Where SPECT and bone scans can pick up early stress reactions, CT may be the most sensitive tool in diagnosis of spondylolytic lesions. Congeni, McCulloch & Swanson, (1997), used CT to investigate the type of lesion and the injury course. 40 athletes with diagnosed spondylolysis lesions by SPECT then had a CT scan. 45% showed a chronic lesion which was managed symptomatically while 40% had an acute lesion with identified healing which was managed with a brace. The authors also question the use of SPECT as a fracture diagnosis tool as a 15% false positive was also found in the fracture diagnosis. SPECT and CT should be complementary to each other to fully understand the extent of the lesion.

 

MRI is another possible method of investigation. Diagnosis often relies on radiographs and CT, both of which are not reliable in early detection and bone scans or SPECT which although sensitive in early diagnosis have high exposure to radiation and are time consuming. Yamane, Yoshida & Mimatsu, (1993), have used MRI to shown a hypointense area on T₁ weighted images before the appearance of a spondylolytic lesion. However Kujala, Kinnunen, Helenius, Orava, Taavitsainen & Karaharju, (1999) found that bone scan was more sensitive than MRI at identifying pars interarticularis stress reaction. The future of imaging especially with regard to pars stress lesions seems to indicate that MRI is becoming more popular. It currently has a high negative prediction value (Saifuddin & Burnett, 1997) and as the cuts get thinner the positive prediction value will rise. It also has the added advantage of less radiation exposure and is currently quite accessible.

 

Imaging protocol seems to follow a similar format. Initially patients receive anteroposterior, lateral and oblique radiographs followed by SPECT.  If SPECT shows diffuse uptake, they are normally treated as a stress reaction. Those showing focal uptake receive a CT scan to further define the anatomy however MRI may be considered over SPECT where patients have had pain for more than six weeks.

 

Young athletes involved in sports and activities which predispose them to pars interarticularis stress injuries need to be carefully observed. Athletes and young athletes especially, may ignore painful symptoms in the pursuit of athletic success. Early diagnosis of pars interarticularis stress reactions is especially important in achieving optimal recovery and prevention of disability later in life. Sairyo, Katoh, Sasa, Yasui, Goel, Vadapalli, Masuda, Biyani & Ebraheim, (2005) found that in 13 athletes with unilateral spondylolysis; diagnosed by CT, 6 had early stage spondylolysis with no contralateral complications while the 7 athletes who has progressive or terminal stage unilateral spondylolysis showed signs of contralateral involvement. This indicates that if unmanaged, a unilateral lesion will likely progress to a bilateral lesion. Unilateral stress reactions are fairly common (Jackson, et al, 1981); however unilateral spondylolysis only occur in about 10% of spondylolysis lesions, the majority being bilateral (Rossi & Dragoni, 2001). This suggests that once a unilateral stress reaction becomes a stress fracture, it progresses quickly to a bilateral stress fracture in the majority of cases.  Gregory et al., (2005) speculate that unilateral stress reactions progress to incomplete fracture before becoming complete fractures. Once a unilateral stress fracture has become complete, the contralateral side almost always becomes involved creating a bilateral spondylolysis. This is possibility due to the instability in the vertebral ring which stresses the contralateral pars interarticularis. Future research may investigate the effects pars lesions have on the surrounding structures and how this translates if the integrity of the vertebral ring is affected.

 

The progression of spondylolisthesis was investigated by Muschik et al., (1996). They found a mean displacement of approximately 10% over a period of 4.8 years. 86 athletes were investigated where 38% showed an increased displacement, 42% showed no progression and 9% showed a decreased in displacement. All the athletes continued to participate in competitive sport over the entire period without any symptoms suggesting asymptomatic adolescents with spondylolysis or spondylolisthesis should not be limited from participating in sport. Ikata, Miyake, Katoh, Morita & Murase, (1996) considered the progression from spondylolysis to spondylolisthesis and concludes that younger athletes are more likely to have a slip. This poses the question whether end plate disruption is a result or the cause of spondylolisthetic changes but could also indicate the possibility to predict future further progression. 

 

Common forms of non-operative management for spondylolysis normally consist of a period of rest or restricted activity and can also include physiotherapy modalities, immobilisation and electrotherapy. The main aim of the treatment is to relieve lower back pain by off loading the area with the stress reaction or stabilizing a fracture with or without fibrous union. Whether a stress reaction or spondylolysis almost all authors suggest a period of rest from the aggravating activity. Jackson et al, (1981) found that adolescent athletes with unilateral pars stress reaction diagnosed by bone scan made a full recovery and return to sport in an average of 7.3 months by limiting the aggravating activities and rest. All the follow-up investigations appeared normal indicating excellent recovery can be achieved with early intervention.

 

A stress reaction identified with a bone scan or SPECT but no radiographic evidence of a stress fracture should be treated with activity restriction to pain free limits and anti-lordotic bracing for 2-3 months to allow the stress reaction to heal fully (Bell, Ehrlich & Zaleske, 1988). A conditioning programme should be undertaken before returning to full sport. Optimal results would include bony union prior to return to sporting activity. Sairyo et al., (2005) examined 13 young athletes (14.8 years) for unilateral spondylolysis using CT and MRI. The individuals were divided into groups depending on the stage of unilateral spondylolysis detected. All individuals in the early stage spondylolysis group showed no signs of contralateral involvement while the subjects in the progressive and terminal stage spondylolysis group showed stress reactions at the contralateral pars interarticularis. All individuals underwent non-operative treatment and were investigated again between 3-6 months. All the early stage spondylolysis showed signs of healing while the later stage did not. Unilateral spondylolysis show a greater capacity to heal especially in the early stage however the evidence suggests that a unilateral lesion will quickly affect the contralateral side if left untreated. Early appropriate investigation and intervention is vital in achieving optimal healing.

 

Sys et al (2001) investigated the healing effect of active spondylolysis diagnosis in 34 competitive athletes with normal radiographs and positive bone scans using non-operative treatment. The conservative treatment used was an anti-lordotic brace for 23 hours a day for a period up to 6 months depending to the most recent bone scan. General mobility exercises were initiated when the individuals had no pain with activities of daily living. All unilateral lesions healed with excellent outcome. Over 50% of the bilateral spondylolysis achieved union while unilateral union was observed in the pseudo-bilateral group. The evidence seems to suggest that active stress fractures have the capacity to heal even in bilateral lesions, reiterating the importance of early diagnosis for optimal outcome; however non-bony union does not seem to affect the overall outcome with regarding to return to sport. Miller, Congeni & Swanson, (2004) did a follow up over 11 years on early detection spondylolysis in young athletes using positive bone scans and negative radiographs. They found that none of the 32 individuals who completed the survey required surgery and only required rare medical or manipulative treatment for their backs. The initial treatment consisted of relative rest, a non-rigid lumbar brace and flexion-only trunk strengthening exercises over 8-12 weeks. Initially return to sport was allowed when the individuals were pain free at rest, in hyperextension and during the sporting activity using the brace.

 

Iwamoto, Takeda & Wakano, (2004) reports that 40 athletes, identified by radiograph, who had to discontinue sport due to pain caused by a defect in the pars interarticularis, 35 (87%), could return to original sporting level despite bony non-union within an average of  5.4 months. The treatment consisted of rest and anti-lordotic bracing. El Rassi, Takemitsu, Woratanarat & Shah, (2005), investigated 57 adolescent soccer players with lumbar spondylolysis diagnosed with radiographs. They investigated results of individuals who stopped sport with or without bracing and those who continued playing with and without bracing. The groups who limited their sporting activity with and without bracing had a significantly better outcome than the latter two groups. Bracing alone did not seem to achieve optimal results unlike sport cessation alone which did have excellent results. This indicates that stopping sporting activities for period of time should allow the participant to return to previous sports level yet also questions the benefit of bracing.

 

O'Sullivan, Twomey & Allison, (1997) investigated the use of specific stabilizing exercise in managing pain associated with radiographically diagnosis spondylolysis and spondylolisthesis. 44 patients were divided into 2 groups, 1 which participated in specific contraction of the deep abdominal muscles and co-contraction with multifidus while the other group followed a protocol outlined by their doctor. The result suggest significant decrease in the study groups pain and increased functional level after 3 months up to 30 months compared to the control group whose treatment consisted of medication, massage and other pain relieving modalities. This study involves the general population but the results could be extrapolated to include an active population. Future research could investigate the results of early preventative strategies and how these compare to current studies.

 

Surgical treatment for spondylolysis normally occurs if non-operative management has been unsuccessful and the individual is still in a significant amount of pain which is limiting activities of daily living, which may or may not include sporting activities. If a spondylolisthesis is present, surgical intervention is undertaken if neurological symptoms are present, the slip is progressive or the individual has a grade III defined by the Meyerding scale. Discussion around the specific methods and controversies in the surgical management of this condition are outside the scope of this discussion. Surgical management can consist of a posterolateral fusion or a direct repair of the defect. Direct repair seems to be less popular than a fusion; however there is insufficient evidence of individual improvement compared to fusion (Bono, 2004). Debnath, Freeman, Gregory, de la Harpe, Kerslake & Webb, (2003) investigated the outcome of two different fusion techniques. Of the 22 athletes who underwent the surgical treatment 18 returned to previous sporting activities in an average of 7 months. There is a limited guideline for return to sport after a fusion but most surgeons seem to suggest full return is possible.

 

Spondylolysis and spondylolisthesis are conditions which if left untreated can cause athletes discomfort and potential disability. A clear understanding of the epidemiology and the disorder progression is vital in efficient and effective diagnosis and management. A clearly defined protocol will help to identify early disorders before they progress and better manage symptomatic individuals.

 

Reference List

Beaty, J.H., (1999). Orthopaedic Knowledge Update Six. (1^st Ed). Rosemont: American Academy of Orthopaedic Surgeons. ISBN 10: 0892932111

 

Bell, D.F., Ehrlich, M.G. & Zaleske, D.J., (1988). Brace treatment for symptomatic spondylolisthesis. Clinical Orthopaedics and Related Research, 236, 192–198.

 

Bellah, R.D., Summerville, D.A., Treves, S.T. & Micheli, L.J., (1991). Low-back pain in adolescent athletes: detection of stress injury to the pars interarticularis with SPECT. Radiology, 180, 509-512.

Bono, C.M., (2004).Low-Back Pain in Athletes. Journal of Bone & Joint Surgery of America, 86, 382-396.

Congeni, J., McCulloch, J. & Swanson, K., (1997). Lumbar Spondylolysis: A Study of Natural Progression in Athletes. American Journal of Sports Medicine, 25, 248-253. DOI: 10.1177/036354659702500220.

Debnath, U.K., Freeman, B.J.C., Gregory, P., de la Harpe, D., Kerslake, R.W. & Webb, J.K., (2003). Clinical outcome and return to sport after the surgical treatment of spondylolysis in young athletes. Journal of Bone and Joint Surgery, 85, 244-249. doi.10.1302/0301-620X.85B2.13074

d'Hemecourt, P., Gerbino, P. & Micheli, L., (2000). Back Injuries in the young athlete. Clinical Sports Medicine, 19,663-679.

El Rassi, G., Takemitsu, M., Woratanarat, P. & Shah, S.A., (2005). Lumbar Spondylolysis in Pediatric and Adolescent Soccer Players. American journal of sports medicine, 3, 1688-1693. DOI: 10.1177/0363546505275645

Fredrickson, B.E., Baker, D., McHolick, W.J., Yuan, H.A. & Lubicky, J.P., (1984). The natural history of spondylolysis and spondylolisthesis. The Journal of Bone Joint & Surgery of America, 66: 699-707.

Gregory, P.L., Batt, M.E. & Kerslake, R.W., (2004). Comparing spondylolysis in cricketers and soccer players. British Journal Sports Medicine, 38. 737-742. doi: 10.1136/bjsm.2003.008110

Harvey, C., Richenberg, J., Saifuddin, A. & Wolman, R., (1998). Pictoral review: the radiological investigation of lumbar spondylolysis, Clinical Radiology. 53, 723-728.

Ikata, T., Miyake, R., Katoh, S., Morita, T. & Murase, M., (1996). Pathogenesis of sports related spondylolisthesis in adolescents. Radiographic and magnetic resonance imaging study. American Journal of Sports Medicine, 24, 94-98.

Iwamoto, J., Takeda, T. & Wakano, K., (2004). Returning athletes with severe low back pain and spondylolysis to original sporting activities with conservative treatment. Scandinavian Journal of Medicine and Science in Sports, 14, 346–351. DOI: 10.1111/j.1600-0838.2004.00379.x

Jackson, D.W., Wiltse, L.L. & Cirincoine, R.J., (1976). Spondylolysis in the female gymnast. Clinical Orthopaedics, 117, 68-73.

Jackson, D.W., Wiltse, L.L., Dingeman, R.D. & Hayes, M., (1981). Stress reactions involving the pars interarticularis in young athletes. American Journal of Sports Medicine, 9, 304-312.

Kalichman, L., Kim, D.H., Li, L., Guermazi, A., Berkin, V. & Hunter, D.J., (2009). Spondylolysis and spondylolisthesis: prevalence and association with low back pain in the adult community-based population. Spine, 34, 199-205.

Kujala, U.M., Kinnunen, J., Helenius, P., Orava, S., Taavitsainen, M. & Karaharju, E., (1999).Prolonged low-back pain in young athletes: a prospective case series study of findings and prognosis. European Spine Journal, 8, 480-484.

Kujala, U.M., Taimela, S., Erkintalo, M., Salminen, J.J. & Kaprio, J., (1996). Low-back pain in adolescent athletes. Medicine & Science in Sports & Exercise, 28, 165-170.

McCleary, M.D. & Congeni, J.A., (2007). Current Concepts in the Diagnosis and Treatment of Spondylolysis in Young Athletes. Current Sports Medicine Reports, 6, 62-66

Meyerding, H., (1932). Spondylolisthesis. Surgical Gynaecology and Obstetrics, 54, 371-377.

Micheli, L.J. & Wood, R., (1995). Back Pain in Young Athletes: Significant Differences from Adults in Causes and Patterns. Archive of Paediatric & Adolescent Medicine, 149, 15-18.

Miller, S.F., Congeni, J. & Swanson, K., (2004). Long-Term Functional and Anatomical Follow-up of Early Detected Spondylolysis in Young Athletes. American journal of sports medicine, 32, 928-933. DOI: 10.1177/036354650326219

Muschik, M., Hahnel, H., Robinson, P.N., Perka, C. &  Muschik, C., (1996).Competitive sports and the progression of spondylolisthesis. The Journal of Paediatric Orthopaedics, 16, 364–369.

O'Sullivan, P.B., Twomey, L.T. & Allison, G.T., (1997). Evaluation of Specific Stabilizing Exercise in the Treatment of Chronic Low Back Pain With Radiologic Diagnosis of Spondylolysis or Spondylolisthesis. Spine, 22, 2959-2967

Pennell, R.G., Maurer, A.H. & Bonakdarpour, A., (1985). Stress Injuries of the Pars Interarticularis: Radiologic Classification and Indications for Scintigraphy. American Journal of Roentgenology, 145, 763-766

Rossi, F. & Dragoni, S., (2001). The prevalence of spondylolysis and spondylolisthesis in symptomatic elite athletes: radiographic findings. Radiography, 7, 37–42. doi:10.1053/radi.2000.029

Saifuddin, A. & Burnett, S.J., (1997). The value of lumbar spine MRI in the assessment of the pars interarticularis. , 52, 666-671.

Saifuddin, A., White, J., Tucker, S. & Taylor, B.A, (1997). Orientation of lumbar pars defects: Implications for Radiological detection and surgical management. Journal of Bone and Joint Surgery, 80, 208-211.

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Case study of an International Judoka with Scapho-lunate instability

Introduction

The wrist joint is an intricate system of bones and ligaments allowing a variety of motions while also providing strength and stability (Lewis & Osterman, 2001). It consists of a complex arrangement of intrinsic and extrinsic ligaments which help support the individual bones while biomechanically allowing the transmission for forces to the hand (Howse, 1994). This permits precision, dexterity and strength in the hand and fingers, essential for grasping and participation in a sport such as judo (Amtmann & Cotton, 2005). Judo is a sport in which a judoka (judo athlete) grapples with an opponent in an attempt to create an offensive or counter-offensive advantage while defending against a similar assault (Green, Petrou, Fogarty-Hover & Rolf, 2007). An important aspect of judo is a judoka’s ability grip an opponent’s jacket or gi, while attempting to throw them to the ground with impetus (Amtmann & Cotton, 2005). Although grip technique plays a role in fight control, grip strength is a vital component in the domination of the match and improves the judoka’s chances of success (Amtmann & Cotton, 2005).

Due to the contact nature of judo, athletes tend to have a high risk of injury (Laskowski, Najarian, Smith, Stuart & Friend, 1995), however, Green, Petrou, Fogarty-Hover & Rolf, (2007) report a surprisingly low incidence of wrist injuries among judokas, considering the nature of the sport. Most wrist injuries, including scapho-lunate ligament injuries, are traumatic in nature (Lewis & Osterman, 2001), especially in this population group. Fractures in and surrounding the wrist are the most common diagnosed injuries (Goldberg, Strauch & Rosenwasser, 2006) and relatively common in judo, however wrist sprains are the most commonly reported injuries to the wrist among athletes in contact sports (Rettig, Ryan & Stone, 1992 cited by Goldberg et al., 2006). Due to radiographic evidence, fractures tend to be managed early, while no fracture may seem ‘insignificant’ and simply be referred for rehabilitation (Lewis & Osterman, 2001). This often leads to missed or under-diagnosis of ligament injuries and possible premature return to participation, which can take a potential minor injury and progress it to a more complex injury requiring more extensive surgical intervention, rehabilitation, and possibly a less favourable outcome.

Mechanism of injury

It is not entirely clear the exact mechanisms which lead to scapho-lunate instability but the most likely cause is a fall on an outstretched hand (Lewis & Osterman, 2001). Researchers have suggested that an axial load is applied through the hypothenar region with the wrist in extension, supination and ulnar deviation causing the capitate to be driven between the scaphoid and the lunate (Goldberg, et al., 2006). This displaces the scaphoid in a dorsal and radial direction and the lunate in a volar and ulnar direction, resulting in attenuation, a partial or a complete tear at the scapho-lunate interosseous ligament (Mayfield, 1980). This mechanism of injury which results in a scapho-lunate instability injury can be applied to judo due to the throws and falls sustained in training and competitions.      

Diagnosis

The initial clinical appearance of scapho-lunate instability is normally reported as pain and tenderness over the dorsal radial aspect of the wrist and is often in the region of the scapho-lunate ligament (Bozentka, 1999) (Figure 1). There is also a loss of motion and swelling (Lewis & Osterman, 2001). A good subjective examination is important to determine the hand and wrist position when the injury occurred and how the symptoms are reproduced (Lewis & Osterman, 2001). Although the typical mechanism of injury is a fall on outstretched hand other factors like repetitive trauma from, for example crutch walking over an extended period, could also contribute to the development of scapho-lunate instability (Bozentka, 1999) and could be associated to an athlete who has a history or lower limb trauma requiring crutches.

 

Figure 1 – Scapho-lunate interosseous ligament

 

 

 

 

 

  http://handspecialists.com/Pain/wrist_sprains.html, (2011)

The objective examination will present with mild or no swelling surrounding the scapho-lunate region (Manuel & Moran, 2007). Tenderness can be palpated over dorsal scapho-lunate gap distal to Lister's tubercle (Goldberg, et al., 2006). Grip strength has been reported to be about 67% compared to the contra-lateral side. This can be used as a useful return to play measure (Prosser, Herbert & LaStayo, 2007). The most widely reported used provocation test appears to be the Watson scaphoid shift test, being used by 80% of hand therapists in the testing for scapho-lunate instability in one recent survey (Prosser, et al., 2007) however; (LaStayo & Howell, 1995) reported a low sensitivity and specificity. The test is positive if the scaphoid is subluxated out of the distal radial fossa with a painful clunk when the wrist is brought from ulnar to radial deviation with pressure over volar distal pole of the scaphoid (Watson, Ashmead & Makhlouf, 1988 cited in Goldberg, et al., 2006). It is important to eliminate any differential diagnosis which may be masquerading as scapho-lunate instability (Lewis & Osterman, 2001).  
 

Following the provisional clinical diagnosis this athlete should undergo radiographic investigation. The available evidence seems to suggest that certainly two views should be included and possibly stress radiographs if the initial views are normal (Manuel & Moran, 2007). An posteroanterior view may reveal a widening of the scapho-luntate joint space and the scaphoid ring sign, indicating the scaphoid has collapsed into flexion (Cautilli & Wehbe, 1991) (Figure 2) while the lateral view may show a rotatory subluxation of the scaphoid (Manuel & Moran, 2007). Ozcelik, Gunal & Kose, (2005) found that stress radiographs are very useful particularly in identifying dynamic instability but in all cases, any abnormality needs to be compared to the contra-lateral side.

Figure 2 - Radiographic Findings in Scapho-lunate Instability,

http://www.eorif.com/WristHand/DISI.html#Anchor-Radiographic-49575, (2011)

1) Cortical ring sign. 2) Terry Thomas sign indicating an enlarged scapho-lunate gap and interosseous ligament disruption. 3) Scaphoid appears foreshortened. 4) Distal radius. 5)The lunate should be quadrilateral in shape but may appear triangular with scapho-lunate instability.

Although there are a number of different modalities available to identify and grade scapho-lunate injuries (Manuel& Moran, 2007) including bone scintigraphy, arthrography and magnetic resonance imaging, none are highly sensitive (Herbert, Faithfull, McCann & Ireland, 1990) & (Schadel-Hopfner, Iwinska-Zelder, Braus, Bohringer, Klose & Gotzen, 2001) and should be excluded in favour of an arthroscopy. Arthroscopy has been shown to be more specific in identifying scapho-lunate interossious ligament derangement (Cooney, Dobyns & Linscheid, 1990). This intervention has also allowed surgeons to develop a grading system to describe the extent of the local and associated ligament and articular damage (Kozin, 1999) (Table 1).

Table 1 – Arthroscopic classification of scapholunate ligament injuries (Kozin, 1999)
Grade	Description
I	Attenuation or haemorrhage, no incongruence
II	Incongruence or step-off of carpal space, slight gap less than width of probe
III	Incongruence or step-off of carpal space, probe passed between scaphoid and lunate
IV	Incongruence or step-off of carpal space, scope (2.7mm) passed through gap between scaphoid and lunate

Classification

The severity of the injury can be described using a four-stage classification. The earliest stage is pre-dynamic instability which is characterized by partially ruptured or attenuated scapho-lunate ligament which leads to abnormal scapho-lunate motion especially in flexion and extension (Short, Werner, Green, Masaoka, 2002). This stage is often missed as pain is the most common symptom but plain and stress radiographs present as normal. However if left untreated the secondary stabilizers become involved leading into stage two, dynamic instability (Manuel & Moran, 2007). Dynamic instability is again characterized by a partially ruptured ligament however the scapho-lunate gap is increased under stress loading as the capitate is forced into the scaphoid and lunate,  even though plain radiographs  may appear normal (Trail, Stanley & Hayton, 2007).

Static instability is the third stage and usually involves significant damage to the scapho-lunate ligament as well as the secondary support ligaments (Short, Werner, Green, Sutton & Brutus, 2007). This stage is typically diagnosed by plain radiographs indicating a scapho-lunate gap of greater than 3mm, a scapho-lunate angel of greater than 70° and by arthroscopy (Manuel & Moran, 2007). The lunate may also assume its natural dorsiflexed position associated to the triquetrum while the scaphoid assume a palmerflexed position creating a dorsiflexion intercalated segment instability (DISI) (Wright & Michlovitz, 1996). It has been reported that static instability ultimately leads to scapho-lunate advanced collapse (SLAC), the final degenerative stage (Trail, et al., 2007) associated to altered biomechanics. It is not clear how long this progress takes and the extent of the original injury (O’Meeghan, Stuart, Mamo, Stanley & Trail, 2003), but this is not the focus of this report.

Recommendation

The management of this judoka depends almost entirely on the results of the examination and the investigation (Sivananthan, Sharp & Loh, 2007). There is limited information pertaining to the time lapse since the aggravating event but for the purpose of this report two plausible scenarios will be discussed. In the case where the judoka presents with pre-dynamic or dynamic instability, conservative management should be the first consideration (Lau, Swarna, & Tamvakopoulos, 2009). Linscheid, Dobyns, Beabout & Bryan, (1972) suggest that where the 80% of range of movement and grip strength were conserved, compared to the contra-lateral side and the disability is minor, no treatment is required. However, this was an isolated case and most other untreated cases involving individuals with dynamic instabilities resulted in lifestyle modifications as well as discomfort at rest and during activity for at least 18 months following the injury. None of the cases showed accelerated degeneration or SLAC even after several years (O’Meeghan, et al., 2003).

A case can be made for non-intervention, in this situation where grip strength is preserved and the disability is minor. He is unlikely to be pain and symptom free but may feel he can ‘push through it’ and the opportunity to participate at these competitions may inspire this consideration. This should be dissuaded due to the potential progression of the injury status, requiring more aggressive intervention with a less favourable outcome at a later stage potentially affecting his later sporting and personal career as well as his social lifestyle.

If this judoka has a dynamic instability where the anatomical reduction was maintained, conservative management should consist of immobilization in plaster for a period of six to eight weeks, preferably initiated within four weeks of the injury (Trail, et al., 2007). Manuel & Moran (2007), state however, that scapho-lunate alignment is almost impossible with casting alone. Darlis, Kaufmann, Giannoulis & Sotereanos, (2006) felt that with this group, arthroscopic debridement and ‘K’ wire fixation with casting were better options while Weiss, Sachar & Glowacki, (1997) indicated that 85% of partial tear patients who underwent debridement were completely satisfied with the results. Following this period of immobility, active range-of-motion exercises, focusing on flexion, extension and forearm supination as well as gentle strengthening across the wrist can be started (LaStaypo, Michlovitz & Lee, 2007). Weight bearing and gripping activities need to be avoided to prevent damage to the healing ligament (Wright & Michlovitz, 1996). Proprioceptive re-education of flexor carpi radialis can be useful as it is the only potential dynamic stabilizer of the scaphoid (Jantea, An, Linscheid & Cooney, 1994). Gentle exercises using sponge or putty can help develop grasp strength without exceeding ligament integrity and pain tolerance (LaStayo, et al., 2007) before gradual return to normal activity.  

Following this protocol the judoka will likely be unavailable for the Four-Nations tournament in 12 weeks. He will be in the final phase of his rehabilitation programme with his general fitness and conditioning at pre-injury levels, however his grip strength and technical aspects may require further improvement. He should be available for the already qualified World Championships in six months bar any setbacks.  The goal for the strength and conditioning coach should be to give this judoka the best opportunity to maintain or exceed the training levels he has worked so hard to develop (Dooman & Jones, 2009). Following any injury certain specific exercises need to be substituted for traditional core exercises to allow the athlete to maintain the highest fitness level possible. While cardiovascular exercise such as running and bike work pose minimal problems in maintaining aerobic and anaerobic levels, resistance exercises using weights do. Judo is a sport which requires strength and power as well and a good aerobic-anaerobic capacity (Amtmann & Cotton, 2005). The detraining effect following the management of this wrist injury will leave this judoka significantly weaker (Mujika, & Padilla, 2000), requiring a large amount of resistance training in a short time frame to be prepared for the World Championships unless substitution exercises are introduced (Table 2). Using similar exercises will minimize the athlete’s performance drop-off on return to normal training; limiting the detraining effect and making re-entry into practice more seamless (Dooman & Jones, 2009). 

Table 2 – Resistance exercise substitution (Dooman & Jones, 2009)
Exercises	Sets	Repetitions	Week 1	Week 2	Week 3	Week 4+
Single arm snatch	4-6	3-5	4x5	5x4	6x3	Repeat
Box Jump	8-12	1-3	12x1	10x2	8x3	Repeat
Reverse lunge	3-5	4-8	3x8	4x6	5x4	Repeat
Bulgarian split squat	3-5	4-8	3x8	4x6	5x4	Repeat
Hyperextensions	3-5	4-8	3x8	4x6	5x4	Repeat
Single arm bench press	3-5	4-8	3x8	4x6	5x4	Repeat
Single arm incline press	3-5	4-8	3x8	4x6	5x4	Repeat

Where static instability or complete scapho-lunate interosseous ligament rupture is present almost all sources agree that surgical intervention is the best option (Wright & Michlovitz, 1996). Although there is some discrepancy of the best method of surgical treatment available, most evidence points to ligament repair for best results (Manuel & Moran, 2007) using ‘K’ wires to hold the scaphoid in position (Wright & Michlovitz, 1996). The patient is in an immobilization cast for eight weeks before removal of the ‘K’ wires followed by splinting for a further four weeks. Active range of motion exercises are progressed as soon as possible without compromising the surgical stability (Wright & Michlovitz, 1996) before passive range of motion exercise are introduced about a month later. Isometric exercises leading to concentric exercises are progressed about four to six months following the surgery (Manuel & Moran, 2007) followed by careful progression of grip strength. Return to participation should not occur before six months and only when cleared to do so.  

A static instability injury will cause significant pain and weakness leading to deficits in his ability to train and compete.  Non-intervention seems a doubtful opinion, with surgery the most likely intervention. He will not be available for the four-Nations or the World Championships and will be able to resume full training after six months following no setbacks.   

Prevention recommendations

It is clearly evident from the available research that wrist sprains are not common in judo (Green, et al., 2007). This may be an under-estimation as most research is conducted during major competitions and focuses on major injuries such as fractures, dislocations and tendon rupture (Junge, Engebretsen, Mountjoy, Alonso, Renström, Aubry & and Dvorak, 2009), possibly neglecting minor injuries which show no sign of trauma (Lewis & Osterman, 2001). The evidence also seems to suggest that most injuries in judo occur during training (Kujala, Taimela, Antti-Poika, Orava, Tuominen & Myllynen, 1995) and while these injuries are reported (Goldberg et al., 2006), it is possible that medical staff may under-estimate the extent of a ‘simple wrist sprain’ (Manuel & Moran, 2007), especially with no indication of trauma on investigation while athletes may under-report injuries in an effort to continue to participate (Birrer & Birrer, 1983).

Prevention is an essential aspect in protecting judoka’s from wrist injuries (Amtmann & Cotton, 2005). Even though there is no muscle attachment directly attached to the scaphoid or lunate (Trail, et al., 2007), strength and conditioning are important aspects protecting a judoka from getting injured (Table 3). Programmes developed to improve the strength around the wrist and grip may not only assist the judoka’s ability to fight but may also offload the stress on the wrist in a situation where a fall on an out stretches hand occurs off-setting the extent of the possible injury (Amtmann & Cotton, 2005).

Table 3 - Interchangeable wrist/grip exercises (Amtmann & Cotton, 2005)

·  Wrist curls & reverse wrist curls (barbell or dumbbell) · ‘Thick bar’ wrist curls & reverse wrist curls (barbell or dumbbell) · Farmer’s walk (dumbbells); walk with heavy dumbbells for as long as the possible. · Wrist rollers (clockwise & anti-clockwise) · Judo-gi pull-ups (flexed or straight arm); pull-ups using an old gi or a towel hanging from the pull-up bar.

It is vital to protect judoka’s from high risk injury situations in training. Injuries occur when athletes are outmatched in weight and ability, as well as poor conditioning and fatigue (Amtmann & Cotton, 2005). Good principals are to follow a comprehensive and balanced strength-training program. Conduct hard randori (freestyle practice) sessions in the first half of practice, or make sure the conditioning level of the athletes is high before conducting hard randori in the second half of practice and focus on technical mastery in the areas of throwing, falling, hold-downs, and arm-locks (Amtmann & Cotton, 2005).

It is important to remember that this condition is mostly traumatic in nature in this athlete group (Lewis & Osterman, 2001); suggesting that although rare, injuries are inevitable. It is essential that all wrist injuries are reported, properly assessed and managed appropriately (Goldberg et al., 2006). Following that, all athletes should be observed for any favouring or protecting during competition or training (Lewis & Osterman, 2001). Any rehabilitation programmes needs to prepare the judoka for full return to competition focusing on all aspects of the sports including, strength, conditioning and appropriate energy systems and not just the injury (Amtmann & Cotton, 2005) (Table 4).

Table 4 – Prehabilitation weight circuit programme (Amtmann & Cotton, 2005)
1. 1 min rope jump	2.  Leg extension	3.  Leg curl
4. Bent-knee situps	5.  Neck cycle	6.  Overhead press
7. Lat pull-down	8.  Bench press	9.  Dumbbell curl
10.Wrist curl	11. Wrist rollers	12. Leg press
·         Upper-body exercises - 12–15 repetitions ·         Lower-body exercises - 12–20 repetitions. ·         With little to no rest.

Conclusion

Scapho-lunate instability is a complex condition requiring early diagnosis for best results and long term success. A good understanding of the injury and the sport is vital in prevention and limitation of potential future and current injuries. It is clearly an unfortunate outcome for this particular judoka as he has the chance to compete at the highest level in his chosen sport for his country. However the long term debilitation seems to outweigh the short term prospects to compete and while this may affect the judoka’s short term goals it gives him the best opportunity for short and long term improvement.   

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By: NBrink