RESUMEN
Unexplainable knee pain may follow knee replacement surgery. The popliteal tendon should be evaluated as a possible cause of lateral knee pain and dysfunction after knee arthroplasty. The tendon can snap over or impinge on lateral osteophytes or prominent femoral components and produce mechanical symptoms and pain. Ultrasound-guided injections may confirm the diagnosis and provide symptomatic relief in some patients. Those who respond well to injections and in whom conservative management ultimately fails may be offered arthroscopic release of the popliteal tendon. We present the arthroscopic technique for popliteal tendon release in a symptomatic patient whose pain resolved immediately postoperatively. We recommend the use of an anterolateral viewing portal and an accessory lateral working portal to access the posterolateral knee. There can be extensive scar tissue overlying the popliteal tendon after arthroplasty. Arthroscopic tendon transection and excision comprise a reliable procedure for popliteal tendon impingement after knee arthroplasty without compromising knee stability.
RESUMEN
INTRODUCTION: Placement of intrathecal opioid pumps (ITOP) for chronic pain is a rare, but described cause of progressive spinal deformity. Over the last two decades there has been several suspected cases at our institution. In this case series, we described the apparent association between placement of an intrathecal opioid pump and progression of spinal deformity. METHODS: The medical records of a single surgeon working at a single institution were retrospectively queried for patients seen between 1995-2010 to identify patients with spinal deformity and an ITOP. All hospital records including notes, radiographs, and labs were reviewed and analyzed. Spine radiographs were measured using standard techniques and reported as Cobb angles. This project was IRB approved and no external funding was used. RESULTS: In total, we identified four patients with spinal deformity after placement of an ITOP. These patients were adults, two males and two females (ages: 48-80 years), with a unique medical history. Each participant's radiographs showed a progression of the spinal deformity following placement of ITOP. All patients underwent subsequent posterior spinal fusion for treatment of their progressive spinal deformities. CONCLUSION: In this series, we have shown an apparent association between the placement of ITOP and progression of deformity in both patients with and without existing spinal deformity. While it is impossible to discern causality, all patients in our series had radiographic and clinical evidence of spinal deformity progression after placement of intrathecal pumps. These findings may raise awareness of this rare, but major, complication. In those performing pump placement, we recommend continued clinical and radiographic monitoring, through routine follow-up. LEVEL OF EVIDENCE: Level 4--Case series; case control study (diagnostic studies); poor reference standard; analyses with no sensitivity analyses.
