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