Distal femoral replacement in periprosthetic fracture around total knee arthroplasty.

INTRODUCTION: Total knee arthroplasty is a common orthopaedic procedure in the UK; consequently, revision surgery and periprosthetic fractures are increasing in incidence. Strategies for management of these cases include non-operative strategies, internal plate fixation and revision of the distal femoral component. One under-reported practice is to perform distal femoral replacement in cases with poor distal femoral bone stock. MATERIALS AND METHODS: The department's electronic database was searched for all patients undergoing revision of total knee arthroplasty. From these, all patients having distal femoral replacement for periprosthetic fracture around the distal femoral component using the Stryker Global Modular Replacement System (GMRS) implant were filtered. A retrospective analysis of the patient notes was performed to examine the patient demographics, surgical factors and postoperative complications. Postoperative scores were performed for these patients. RESULTS: From 2005 onwards, 11 patients (mean age 81 years, range 61-90 years) had their implants revised with a distal femoral replacement for periprosthetic fracture with associated poor bone stock. Follow up was for a mean of 33 months (range 4-72 months). One of these patients died of causes unrelated to their operation. Of the rest, all implants survived without the need of re-operation. The mean postoperative Oxford Knee Score for these patients was 22.5 (range 5-34). CONCLUSIONS: Distal femoral replacement for patients with fracture around a total knee arthroplasty has been performed in our department with few complications and acceptable functional outcomes. It is a technically challenging operation and it should be a salvage procedure reserved for patients with poor bone stock and low demands where other methods of fixation are not suitable. LEVEL OF EVIDENCE: IV.

Time to surgery and 30-day morbidity and mortality of periprosthetic hip fractures.

BACKGROUND AND AIM: The management of femoral periprosthetic fractures following hip replacement surgery is a complex and challenging situation. Whilst the early complications for both primary hip arthroplasty and proximal femoral fracture surgery have been widely documented, there is a paucity of published data regarding early outcomes following periprosthetic fracture surgery. Delay to surgery for native proximal femoral fractures has been clearly documented as a predictor towards adverse outcome. This study therefore aims to correlate the timing of operative intervention with the complication rate following periprosthetic fracture surgery. In addition, the study aims to identify further factors in the perioperative period that positively predict a poor postoperative outcome. METHODS: Sixty patients who were operatively managed for a femoral implant periprosthetic fracture were identified and each case assessed retrospectively. RESULTS AND CONCLUSION: There was an overall complication rate of 45% including a 30-day mortality of 10%. An abbreviated mental test score of 8 out of 10 or less and a delay to surgery of >72h were found to be significant risk factors for adverse outcome. Both the patient cohort in this study and the predictors for poor postoperative outcome were comparable to those for native proximal femoral fractures.

Ankle arthrodesis for failed total ankle replacement.

Between 1999 and 2005, 23 failed total ankle replacements were converted to arthrodeses. Three surgical techniques were used: tibiotalar arthrodesis with screw fixation, tibiotalocalcaneal arthrodesis with screw fixation, and tibiotalocalcaneal arthrodesis with an intramedullary nail. As experience was gained, the benefits and problems became apparent. Successful bony union was seen in 17 of the 23 ankles. The complication rate was higher in ankles where the loosening had caused extensive destruction of the body of the talus, usually in rheumatoid arthritis. In this situation we recommend tibiotalocalcaneal arthrodesis with an intramedullary nail. This technique can also be used when there is severe arthritic change in the subtalar joint. Arthrodesis of the tibiotalar joint alone using compression screws was generally possible in osteoarthritis because the destruction of the body of the talus was less extensive. Tibiotalocalcaneal arthrodesis fusion with compression screws has not been successful in our experience.

Delayed repair of the quadriceps using the Mitek anchor system: a case report and review of the literature.

Extensor mechanism disruptions are relatively uncommon knee injuries. Within this group, delayed treatment is an infrequent but difficult clinical situation. Fibrous degeneration, muscle contraction and subsequent hiatus present a challenge to the orthopaedic surgeon. We present an unusual case of a successful delayed repair using the Mitek anchors system (Mitek Products Inc., a division of Ethicon Inc., Westwood, Massachusetts).

A biomechanical comparison of the Mitek RapidLoc, Mitek Meniscal repair system, clearfix screws and vertical PDS and Ti-Cron sutures.

The aim of this in vitro study was to measure and compare the biomechanical properties and mode of failure of the five different methods of meniscal repair. Reproducible tears were created in 50 bovine medial menisci and repaired in a standardized fashion with one of the following devices: the RapidLoc meniscal repair device (Mitek Products, Westwood, MA), an 8 mm Mitek meniscal repair system (Mitek Products, Westwood, MA), Clearfix screw (Innovasive Devices, Marlborough, MA), a single vertical mattress suture of 2-0 Ti-Cron (Ethicon, Massachusetts) and a vertical mattress suture of No. 1 PDS II (Johnson and Johnson Int.). The repairs were tested by single cycle load to failure in a materials testing machine. The mean loads to failure for each of the repair groups were as follows: Mitek RapidLoc 44.9 N, Mitek meniscal repair system 20.3 N, Clearfix screw 37.4 N, vertical Ti-Cron 66.1 N and vertical PDS suture 103.0 N. The mean load to failure was significantly greater with PDS vertical sutures than with other techniques (P<0.05). The Mitek RapidLoc had the least extension at failure (14.8 mm) (P<0.05). This study confirms meniscal repair with vertical PDS sutures confers the highest biomechanical stability and that the new Mitek RapidLoc device offers improved load to failure than the previous generations.

Subungual exostosis following toe nail removal--case report.

Removal of toe nail is a minor procedure that can be under ring block with no significant complications. We report the case of a young lady who developed a rapidly growing subungual exostosis on her right great toe following nail removal. Inadvertent iatrogenic injury to the nail bed and underlying phalangeal periosteum during nail removal might have triggered off rapid bone growth resulting in the large exostosis. To our knowledge, this aetiology for subungual exostosis formation has not been reported before.

The role of MRSA screening in joint-replacement surgery.

The aim of this prospective study was to determine the effect of screening for methicillin-resistant Staphylococcus aureus (MRSA), in patients undergoing total hip and knee replacements, on reducing hospital-acquired infections and the length of hospital stay. We included 395 patients admitted to the elective orthopaedic ward for hip and knee replacements (knee 210; hip 185) from 16 October 2000 to 15 October 2001. Group 1 included 164 admissions before 16 April 2001 when MRSA swabs were not compulsory. Group 2 included 231 admissions after 16 April 2001 when axillary, nasal and groin swabs had to be negative for MRSA. Four patients in group 1 had post-operative MRSA infection compared with none in group 2. The mean length of hospital stay decreased significantly from 10.43 days +/- SD 4.2 days in group 1 to 9.47 days +/- SD 2.6 days in group 2. There was a significant reduction in the incidence of hospital-acquired infections following the introduction of pre-admission screening.

The effect of tibial implant size on post-operative alignment following medial unicompartmental knee replacement.

We have retrospectively reviewed a consecutive series of 71 medial unicompartmental knee replacements in 56 patients performed between 1991 and 1996 by a single surgeon. The aim of this study was to quantify the amount of correction in the tibiofemoral angle, which is achievable with each thickness of polyethylene tibial insert. Our results have shown that the amount of correction which can be expected with an 8 mm, 10 mm, 12 mm and 14 mm insert are 5.3 degrees, 4.8 degrees, 6.6 degrees and 9.5 degrees, respectively. These results will act as a useful reference for surgeons who perform this procedure.

Instability of the neonatal hip: the role of early or late splintage.

From January 1992 to December 1997, 59 dislocatable hips (37 children), confirmed by ultrasound, were splinted by Pavlik bracing within 2 weeks of birth. The majority were splinted within 1 week. From January 1998 to December 1999, 16 dislocatable hips (11 children) were evaluated by ultrasound and were not initially splinted but were followed up by serial ultrasound. They were splinted if they did not spontaneously stabilise on ultrasound. None of those patients treated by immediate splintage between 1992 and 1997 have subsequently required surgical intervention. Two of the infants treated between 1998 and 1999 (12% of the hips) later required a surgical procedure on the hip joint or proximal femur (p=0.049, Fisher's exact test). Nine out of 16 hips required splintage at a later date. We would not advocate delayed observation by ultrasound of unstable hips after 2 weeks of age. A clinically unstable hip should be assessed by ultrasound within 2 weeks of birth. If it is unstable on ultrasound, it should be splinted for 6 weeks. There is no need to wean off the splint.

Migration of a broken meniscal arrow: a case report and review of the literature.

Meniscal repair is a common procedure that can be performed by the inside-out, outside-in, and all-inside techniques. The all-inside technique using the meniscal arrow is increasingly popular. We report a case in which a broken segment of a meniscal arrow was found on exploration of a subcutaneous swelling around the knee three weeks following meniscal repair.