Beware of the hot swollen calf following knee replacement surgery: it might not be a deep vein thrombosis.

We report the case of a 77-year-old woman who presented with a 10-day history of increasing swelling and erythema of her right calf and popliteal areas 12 years after bilateral total knee replacements. Deep venous thrombosis (DVT), cellulitis or possible deep sepsis as a result of the knee replacement were the initial differential diagnoses. Due to clinical deterioration, exploration and radical debridement were performed and a 1.5 L collection of pus was identified through a small posteromedial proximal tibial bone defect adjacent to the tibial component, extending between gastrocnemius, soleus and into the distal calf. The procedure was extended to a first stage revision (complete implant and cement removal). Although leg swelling is common in joint infections secondary to knee swelling as a result of the inflammation, synovitis and/or knee effusion response, this case highlights the need to consider additional pathology such as deep abscess formation or DVT in these types of presentations.

Knee arthroplasty with a medial rotating total knee replacement. Midterm clinical findings: a district general experience of 38 cases.

BACKGROUND: The Medial Rotating Knee replacement (MRK) was first used in 1994, reporting high rates of satisfaction. It is designed to replicate natural knee kinematics and improve stability and function. There are limited studies on the mid-term clinical outcomes, in particular in a district general hospital (DGH) environment. This is the first study that we are aware of that evaluates the learning curve of the implementation of this knee system in this environment. PATIENTS/METHOD: Between 2007 and 2009 we performed 38 consecutive MRK replacements (MAT ORTHO, UK) in 36 patients. The mean follow-up was four years. Patients were evaluated clinically, using OKS and patient questionnaire and radiographically (good/acceptable/poor) to assess outcome. RESULTS: Mean age was 73.0 years. Mean pre-operative OKS was 17.7 (range 8-29), which rose to 38.1 (range 23-48) at latest follow up (p<0.005). Overall 71% of the patients were either satisfied (29%) or very satisfied (42%). 81% felt an improvement of the ability to go up or down stairs and 92% felt stable. All poor radiographic and the majority of acceptable outcomes were experienced in the first 50% of cases. CONCLUSION: The MRK can be successfully implanted in a DGH environment. It improves pain and function comparably to standard TKRs, however, subjective improvement may be higher. Radiographic evaluation shows an acceptable learning curve. LEVEL OF EVIDENCE: Level IV case series.

5-Year cost/benefit analysis of revision of failed unicompartmental knee replacements (UKRs); not "just" a primary total knee replacement (TKR).

BACKGROUND: A number of studies suggest that one advantage of a unicompartmental knee replacement (UKR) is ease of revision to a total knee replacement (TKR). We aimed to perform a cost/benefit analysis of patients undergoing this procedure at our centre to evaluate its economic viability. METHODS: From our own prospective joint replacement database we identified 812 consecutive tibio-femoral UKRs performed (1994-2007) of which 23 were revised to TKR (2005-2008). These were then matched to a cohort of primary TKRs (42 patients). Data were collected regarding patient demographics, cost of surgery, clinical outcome (OKS) and follow-up costs at five years. RESULTS: There was no significant difference in implant costs or in length of stay, however tourniquet time was significantly higher in the revision group (average 93 min (UKR) vs 75 min (TKR) p<0.0001). At five years there was no significant difference in clinical outcome between the revision UKR and primary TKR groups, mean OKS 27 and 32 respectively (p=0.20). The revision group had a greater complication and revision rate, attending significantly more follow-up appointments (average 6 (UKR) vs 2 (TKR) p<0.0001) and consultant appointments (average 4 (UKR) vs 0.4 (TKR) p<0.0001). This was translated to significantly higher follow-up costs. CONCLUSION: Revision of UKR to TKR is not universally a straightforward procedure comparable to a standard primary replacement. Despite cost of components not being significantly higher than primary TKR there are multiple hidden follow-up costs. The clinical outcomes are however similar at 5 years.

Aneurysmal bone cyst as a rare cause of spinal cord compression in a young child.

STUDY DESIGN: Case report. OBJECTIVES: To report: 1) one of the youngest cases of aneurysmal bone cysts presenting with cord compression at the cervicothoracic junction with 7-year follow-up; and 2) the technique we used to stabilize such a small spine. SUMMARY OF BACKGROUND DATA: Aneurysmal bone cyst is an uncommon but well-recognized tumor affecting the spine of children. The mean age of presentation is 16 years. It has hardly been reported below the age of 4 years. All data are in the form of case reports or series. Surgical or nonoperative management can be used. Spinal implant systems are not designed for use in very small children. METHODS: Clinical data analysis. RESULTS: A girl presented at age 2 years and 3 months with cord compression at the cervicothoracic junction. After an inconclusive biopsy, a formal excision and reconstruction of the C7 and T1 were performed anteriorly and posteriorly. We used a fibular graft, internal fixation with crossed plates from the maxillofacial implant tray and a Cervifix rod contoured into a rectangle with sublaminar titanium cables. Postsurgery, she had a left Horner syndrome that has never recovered and motor weakness of the right arm that improved but did not fully recover. She developed a staphylococcal infection 6 months postsurgery that was managed by removal of the rectangle. She developed a posterior recurrence 10 months postsurgery, which was managed surgically. Follow-up has been for 7 years without further evidence of recurrence. CONCLUSIONS: Both surgical and nonsurgical management has been advocated for these tumors. The cord compression at presentation forced us toward surgical management. It is likely that observational data are the only evidence available for clinical decision-making. In this case, we were able to obtain good access to the front of the upper thoracic spine by a supraclavicular approach. Tiny plates are available to maxillofacial surgeons that can be adapted for use in the spines of small children.

Septic arthritis of the elbow after chickenpox.

Musculoskeletal complications following chickenpox are rare among immunologically normal children. Septic arthritis after varicella is caused by group A Streptococcus and affects the knee most frequently. We present a case of septic arthritis of the elbow caused by Staphylococcus aureus. We review the English language literature on septic arthritis complicating chickenpox. We conclude that diagnosis and treatment should be carried out according to guidelines on de novo septic arthritis including the early use of magnetic resonance imaging.