Objective: The treatment of Anterior Cruciate Ligament (ACL) instability resulting from incomplete tears or elongation in continuity has been historically treated either conservatively or by graft replacement. The literature is sparce with regard to alternative reparative surgical treatment of this condition. We report our early experience using a thermal shrinkage treatment on 11 consecutive knees suffering from this condition in patients experiencing continuing instability.

Methods: Eleven patients underwent ACL electrothermal monopolar treatment at our institution between 1998 and 1999. All of these patients presented a difference of 6 mm or more when comparing the involved to the uninvolved side using KT-1000 evaluation. They showed ACL incomplete tears or elongation in continuity at the time of the arthroscopic evaluation. A single electrothermal device (Oratec, Oratec Interventions, Menlo Park, CA) was used in all of the cases. Rehabilitation protocol included immobilization and non-weight-bearing for 6 weeks. A one-year minimum follow-up study was conducted in all of the patients following the IKDC rating system.

Results: The overall outcome at a one-year minimum F.U. was normal or nearly normal in all of the patients. They also showed a 30 pound side to side difference less than 5 mm. They were allowed to return to running 3 months after ACL shrinkage and to full unrestricted sports after 6 months.

Conclusions: The thermal repair of ACL-insufficient knees represents an emerging alternative treatment to standard techniques. The primary controindication for this technique is discontinuity of the ligament. Particular attention must be paid to patient compliance during ligament healing in its early stages.

The tissues surrounding 65 cemented and 36 cementless total joint replacements undergoing revision were characterised for cell types by immunohistochemistry and for cytokine expression by in situ hybridisation.

We identified three distinct groups of revised implants: loose implants with ballooning radiological osteolysis, loose implants without osteolysis, and well-fixed implants. In the cemented series, osteolysis was associated with increased numbers of macrophages (p = 0.0006), T-lymphocyte subgroups (p = 0.03) and IL-1 (p = 0.02) and IL-6 (p = 0.0001) expression, and in the cementless series with increased numbers of T-lymphocyte subgroups (p = 0.005) and increased TNFα expression (p = 0.04). For cemented implants, the histological, histochemical and cytokine profiles of the interface correlated with the clinical and radiological grade of loosening and osteolysis.

Our findings suggest that there are different biological mechanisms of loosening and osteolysis for cemented and cementless implants. T-lymphocyte modulation of macrophage function may be an important interaction at prosthetic interfaces.