Randomized controlled trial of osteoconductive fixation screws for anterior cruciate ligament reconstruction: a comparison of the Calaxo and Milagro screws.

PURPOSE: To compare the outcome of 2 bioabsorbable screws for tibial interference fixation in anterior cruciate ligament reconstruction with reference to rate of absorption, osteoconductive properties, and clinical outcome. METHODS: Patients undergoing primary anterior cruciate ligament reconstruction with hamstring autograft in a single unit were invited to participate in this study. Patients were randomized to receive either the Calaxo screw (Smith & Nephew, Andover, MA) or Milagro screw (DePuy Mitek, Raynham, MA) for tibial fixation. Patients were reviewed with subjective and objective evaluation by use of the International Knee Documentation Committee form, Lysholm score, KT-1000 arthrometry (MEDmetric, San Diego, CA), and clinical examination. Magnetic resonance imaging was performed at 1 year and computed tomography scanning at 1 week and at 6, 12, and 24 months. RESULTS: Sixty patients agreed to participate in the study, with 32 patients randomized to the Calaxo screw and 28 to the Milagro screw for tibial fixation. There was no significant difference in subjective or objective clinical outcome between the 2 groups. At 24 months, 88% of Calaxo screws showed complete screw resorption compared with 0% of Milagro screws (P < .001). Tibial cysts were present in 88% of the Calaxo group and 7% of the Milagro group (P = .001). At 24 months, the mean volume of new bone formation for the Calaxo group was 21% of original screw volume. Ossification of the Milagro screw was unable to be accurately assessed as a result of incomplete screw resorption. CONCLUSIONS: Both screws showed similar favorable objective and subjective outcomes at 2 years. The Calaxo screw resorbed completely over a period of 6 months and was associated with a high incidence of intra-tunnel cyst formation. The Milagro screw increased in volume over a period of 6 months, followed by a gradual resorption, which was still ongoing at 2 years. Both screws were associated with tunnel widening, and neither showed evidence of significant tunnel ossification. We conclude that, despite satisfactory clinical outcomes, the addition of "osteoconductive" materials to bioabsorbable screws is not associated with bone formation at the screw site at 2 years. LEVEL OF EVIDENCE: Level I, randomized controlled trial.

Survival of the anterior cruciate ligament graft and the contralateral ACL at a minimum of 15 years.

BACKGROUND: The risks for primary anterior cruciate ligament (ACL) rupture have been established. What is less well known is the risk of graft rupture after reconstruction and also the risk of a primary ACL rupture in the contralateral knee. PURPOSE: To determine the long-term survival of the ACL graft and the contralateral ACL (CACL) after reconstruction and to identify factors that increase the odds of subsequent ACL injury. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: All patients having undergone primary ACL reconstruction in 1993 or 1994 by a single surgeon in a single unit were considered. Patients were contacted to complete a subjective interview by telephone or e-mail questionnaire at a minimum of 15 years after surgery. RESULTS: A total of 755 patients met the inclusion criteria, and ACL reconstruction was performed using a single-incision endoscopic technique with either autologous bone-patellar tendon-bone graft (BPTB; n = 314) or hamstring tendon graft (HT; n = 359) and metal interference screw fixation. Of these patients, 673 (89%) completed the questionnaire; 23% had sustained either a graft rupture or CACL rupture. Expected survival of the ACL graft was 95%, 93%, 91%, and 89% at a respective 2, 5, 10, and 15 years after reconstruction. Expected survival of the CACL was 97%, 93%, 90%, and 87%, respectively. Survival of the ACL graft was less favorable in men than in women (P = .007); ACL graft survival was not significantly different between the HT (88%) or BPTB (91%) groups (P = .149). Rupture of the CACL occurred twice as frequently as graft rupture in the BPTB group (graft survival, 84% vs 89%; P = .003). A positive family history of ACL rupture doubled the odds of both ACL graft and CACL rupture. The mean International Knee Documentation Committee subjective score at 15 years was 85. Return to preinjury sport levels was reported in 73% of patients, and 51% were still participating in strenuous or very strenuous activities at 15 years. CONCLUSION: Fifteen years after ACL reconstruction, expected survival of the ACL graft was 89% and expected survival of the CACL was 86%. Graft choice did not affect ACL graft rupture, but using BPTB increased the risk of CACL rupture compared with HT. Men had a less favorable survival rate of the ACL graft than did women, and a family history of ACL rupture increased the risk of both ACL graft and CACL rupture.

Clinic-based nerve conduction studies reduce time to surgery and are cost effective: a comparison with formal electrophysiological testing.

INTRODUCTION: Carpal tunnel syndrome is the most common compression neuropathy affecting the upper limb. Clinical diagnosis is not always clear and electrophysiological testing can be indicated when considering a patient for decompression surgery. The downside of electrophysiological testing is cost and increased time to surgery. Newer methods of performing nerve conduction studies in clinic have become available. MATERIALS AND METHODS: We investigated the use of a clinic-based, handheld, non-invasive electrophysiological device (NC-stat®) in 71 patients with suspected carpal tunnel syndrome presenting to our hand clinic in a district general hospital. We compared this to a similar cohort of 71 age-matched patients also presenting to our unit in whom formal nerve conduction studies were performed at a local neurophysiology unit. Our outcome measures were time from presentation to carpal tunnel decompression, the cost of each pathway and the practicalities of using the device in a busy hand unit. RESULTS AND CONCLUSIONS: The NC-stat® proved to be a successful device when compared with referring patients out for more formal nerve conduction studies, shortening the time from presentation to surgery from 198 days to 102 days (p<0.0001). It was also cost effective with a calculated saving to the hospital of more than £70 per patient. The device is easy to use and acceptable to patients and no adverse effects were noted.

Arthroscopically induced posterior capsular fibrosis to correct symptomatic hyperextension of the knee.

We present a technical note on 2 patients with post-traumatic symptomatic hyperextension of the knee treated with a new arthroscopic technique. Both patients were of similar ages with similar injuries resulting in an excess of hyperextension at the knee with resulting instability and pain. Both patients had not improved with a variety of nonoperative measures and 1 attempt each at simple arthroscopic debridement of the damaged tissue. Our technique involves carefully scarring the damaged posterior capsule arthroscopically, followed by extension block bracing for 12 weeks. In 2 patients who had not improved with previously described techniques, we achieved a correction of the excess hyperextension with resulting improvement in their symptoms. Two years after surgery, both patients had significantly improved Lysholm and Tegner activity scores and had returned to work. We believe this technique to be reliable and reproducible.