Metacarpophalangeal collateral ligament reconstruction using small intestinal submucosa in an equine model.

Xenogeneic porcine small intestinal submucosa (SIS) is a natural, biodegradable matrix that has been successfully used as a scaffold for repair of tissue defects. The goal of this study was to compare a collateral ligament transection surgically reconstructed with an anchored SIS ligament to a sham-operated control procedure for the correction of joint laxity using an equine model. Ten metacarpophalangeal joints from 10 horses had complete transection of the lateral collateral ligament. In 6 horses, the collateral ligament was reconstructed with a multilaminate strip of SIS anchored with screws into bone tunnels proximal and distal to the joint. The sham controls had similar screws, but no SIS placed. Clinical compatibility and effectiveness were evaluated with lameness, incisional quality, and joint range of motion, circumference and laxity. Ligament structure and strength was quantified with serial high resolution ultrasound, histology, and mechanical testing at 8 weeks. Surgical repair with SIS eliminated joint laxity at surgery. SIS-treated joints had significantly less laxity than sham treatment at 8 weeks (p < 0.001). SIS-treated ligaments demonstrated a progressive increase in repair tissue density and fiber alignment that by week 8 were significantly greater than sham-treated ligament (p < 0.03). SIS-repaired ligament tended to have greater peak stress to failure than sham-treatment (p < 0.07). Cellularity within the ligament repair tissue and inflammation within the bone tunnel was significantly greater in the SIS-treated limbs (p < 0.017). Within the first 8 weeks of healing, SIS implanted to reinforce collateral ligament injury was biocompatible in the joint environment, restored initial loss of joint stability, and accelerated early repair tissue quality. SIS ligament reconstruction might provide benefit to early ligament healing and assist early joint stability associated with ligament injury.

Evaluation of elbow and shoulder problems in professional baseball pitchers.

When a professional athlete injures an elbow or shoulder, the uninjured joint must receive as much attention as the injured joint. Is there a relationship between injury of one joint and subsequent injury of the other joint? In the prospective study reported here, we created a database (a) to determine whether injury to one joint was more likely to result in a problem with the other joint and (b) to analyze for trends and correlations. A survey was administered to all pitchers on a professional baseball team to collect data about shoulder and elbow problems during their careers. Eighty-four pitchers (737 seasons of experience, 52 index injuries) were evaluated. Of the injured players, 27 were treated surgically. Risk for later injury was 4.6 times larger for players who had an index surgery than for those who had not. Of the players who had ulnar collateral ligament (UCL) reconstruction, 42% later sustained a shoulder injury. No player with rotator cuff surgery sustained a subsequent elbow or shoulder injury. There were significantly more upper extremity injuries with right-handed throwers. An elbow injury was more likely to result in shoulder problems, specifically after UCL reconstruction. Players who required surgery were almost 5 times more likely to have a later injury or surgery than players who did not require surgery.