Fifth metacarpal instability and its effect on hamatometacarpal arthritis patterns-a cadaver study.

Osteoarthritis (OA) of the fifth carpometacarpal joint is a rare diagnosis with most cases occurring post-traumatically. The joint's ligamentous supports have not been described extensively; however we know that the volar and intermetacarpal ligaments acts as the primary stabilizers. The major deforming forces on this joint are the extensor carpi ulnaris (ECU) dorsally and the flexor carpi ulnaris volarly, via the pisimetacarpal ligament. The aim of this study was to determine how the different joint stabilizers contribute to fifth carpometacarpal joint stability and biomechanics. We also sought to describe the OA patterns affecting the fifth carpometacarpal joint. A study was performed on 10 embalmed cadavers. The fifth carpometacarpal joint was evaluated biomechanically through ECU traction and sequential transection of the joint stabilizers. Gross macroscopic evaluation of degenerative changes in the articular surface was conducted and graded on a scale of 0-3 (with 0 representing normal cartilage with no visible lesions). Biomechanical data were available from 18 specimens (10 right; 8 left) and arthritic patterns were available from all 20 specimens (10 right; 10 left). Based on the biomechanical data, the proximal and distal intermetacarpal ligaments were found to be major contributors to stability. The volar stabilizer was a minor contributor to stability and the dorsal stabilizer was a minimal contributor to stability. OA was present in 16/20 specimens (80%) with an average arthritis grade of 1.6 on the right hand and 1.0 on the left hand. The most common site of OA was the dorso-ulnar quadrant.

The quality of informed consent obtained for orthopedic surgeries-elective versus trauma: A prospective interview-based study.

BACKGROUND: Orthopedic surgeons routinely obtain informed consent prior to surgery. Legally adequate informed consent necessitates a thorough discussion of treatment options and risks and proper documentation. However, the quality of informed consent in orthopedic trauma patients is an under-researched area. PURPOSE: To assess the quality of the informed consent process in trauma compared with elective orthopedic patients and to assess patients' emotional state at the time of signing consent form. METHODS: Sixty-two consecutive patients undergoing either elective total joint arthroplasty ( N = 32) or orthopedic trauma surgery ( N = 30) were included. The data were collected through personal interviews using a proposed informed consent score. The interviews were held after obtaining the informed consent and before the index procedure. Patients were asked to describe their diagnosis, the surgical procedure, its' benefits, and risks as well as alternative treatments. RESULTS: Mean age differed significantly between elective and trauma group patients (66.1 vs. 51.6, respectively, p < 0.01), while gender and education level were comparable ( p = 0.075, p = 0.55, respectively). The quality of consent was significantly better for patients with post-high-school education compared to elementary education level (consent score: 16.9 ± 4.1 vs. 12.2 ± 5.5, p = 0.021). Patients in the elective group showed an overall higher quality of consent, as reflected by a mean score of 17.03 ± 4.2 versus a mean score of only 13.73 ± 4.7 in the trauma group ( p = 0.005, 95% CI: 1.02-5.57). Specifically, trauma patients demonstrated a lower comprehension of the diagnosis, the benefits of surgical treatment, the possible complications, and the expected postoperative course. CONCLUSION: Patients undergoing trauma surgery are significantly more likely to have an inadequate understanding of the proposed treatment. These findings raise questions concerning the validity of consent from trauma patients.

Reconstruction of chronic abductor deficiency after revision hip arthroplasty using an extensor mechanism allograft.

This study reports the clinical outcome of reconstruction of deficient abductor muscles following revision total hip arthroplasty (THA), using a fresh-frozen allograft of the extensor mechanism of the knee. A retrospective analysis was conducted of 11 consecutive patients with a severe limp because of abductor deficiency which was confirmed on MRI scans. The mean age of the patients (three men and eight women) was 66.7 years (52 to 84), with a mean follow-up of 33 months (24 to 41). Following surgery, two patients had no limp, seven had a mild limp, and two had a persistent severe limp (p = 0.004). The mean power of the abductors improved on the Medical Research Council scale from 2.15 to 3.8 (p < 0.001). Pre-operatively, all patients required a stick or walking frame; post-operatively, four patients were able to walk without an aid. Overall, nine patients had severe or moderate pain pre-operatively; ten patients had no or mild pain post-operatively. At final review, the Harris hip score was good in five patients, fair in two and poor in four. We conclude that using an extensor mechanism allograft is relatively effective in the treatment of chronic abductor deficiency of the hip after THA when techniques such as local tissue transfer are not possible. Longer-term follow-up is necessary before the technique can be broadly applied.

The value of 18-FDG PET/CT in the diagnosis and management of implant-related infections of the tibia: a case series.

BACKGROUND: Positron emission tomography (PET) combined with Computerised Tomography (CT) is gaining ground in clinical settings due to its added value of combined metabolic and anatomical imaging. PET/CT has shown promising results in diagnosing both acute and chronic infection of the axial and appendicular skeleton. PET imaging has an advantage in patients with metallic implants because FDG uptake, in contrast to magnetic resonance imaging (MRI) and standard computed tomography (CT), is not hampered by metallic artifacts. The role of PET/CT in the evaluation of implant-related infections involving the tibia in particular has not been thoroughly studied. PURPOSE: To investigate the usefulness of 18-FDG PET/CT in the diagnosis and treatment of implant-related infections of the tibia following osteosynthesis. METHODS: We reviewed 10 patients who underwent internal fixation to the tibia following trauma (4 open fractures, 6 closed fractures) and presented later with clinical signs of a possible implant-related infection. In evaluating the patients we used standard work-up methods (standard radiographs, lab tests) as well as advanced imaging techniques (PET/CT) in order to confirm the diagnosis and decide upon the preferred treatment. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were then calculated for PET/CTs ability to predict presence of infection using intraoperative cultures as the gold standard. RESULTS: PET/CT validated our working diagnosis 9 out of 10 patients. In particular, it helped distinguish between: infected nonunion (n=4), aseptic nonunion (n=1), soft tissue infection (n=2) and chronic osteomyelitis (n=3). The overall sensitivity and specificity of PET/CT for identifying an osseous infection were 85.7% and 100%, respectively. The PPV and NPV were 100% and 75%, respectively. CONCLUSION: PET/CT is a promising imaging modality that can aid in the work up of patients with suspected implant-related infections of the tibia following osteosynthesis, and may be used as a supportive measure in clinical decision making.

Solitary intraosseous myofibroma of the tibia in an adult patient: A case report.

Myofibromas are mesenchymal tumors showing myofibroblastic differentiation and found most frequently in the head and neck region. While several cases of myofibromas have been reported in adults, they have not been described in long bones of the appendicular skeleton. We describe an otherwise healthy young woman who presented with a progressive incapacitating pain in her right shin. Imaging studies revealed a well-circumscribed osteolytic lesion with slight marginal sclerosis confined to the proximal tibia metaphysis, without a soft tissue component. Surgical intervention was performed and histological examination identified a myofibroma. This case represents an extremely rare occurrence of an intraosseous myofibroma involving a long bone in an adult patient. Although solitary myofibroma is a rare lesion in the skeletal bones of adults we believe it should be included in the differential diagnosis of a solitary lytic mass in bone, especially if it is associated with pain.

Hip arthroplasty with the articular surface replacement (ASR) system: survivorship analysis and functional outcomes.

BACKGROUND: The articular surface replacement (ASR) hip resurfacing system, now withdrawn, has the highest all-cause revision rate (24.2 % at 7 years) compared with other resurfacing brands. We present our experience with the ASR articulation and the implant recall process. METHODS: We reviewed the medical records and examined all 55 patients (57 hips) who had THA by the senior author between March 2005 and November 2008. We recorded the Oxford Hip scores, metal ion levels, need for revision, the indication for revision, and the intra-operative findings. Radiographs were performed at the time of recall to detect component failure. RESULTS: Survival at 5 years with revision for any reason as the endpoint was 85.1 % for all patients. At the time of recall, 10 (17.5 %) of fifty-seven THAs were already revised. Four (40 %) of the ten revisions were performed within 1 month of the operation due to a periprosthetic fracture. Three other revisions were due to avascular necrosis at a mean time of 3.6 years. One patient was revised due to infection. The two remaining revisions were due to ongoing groin pain, in one of whom the cup was found to be loose. CONCLUSIONS: Our data indicate an overall high revision rate, comparable with recently published studies. Even though most of our revisions were attributed to causes that are not specific to the metal-on-metal articulation, we do expect to find more cases of failures in the future. Therefore, continued close clinical surveillance and laboratory monitoring of these patients is warranted.

Surgical challenges and clinical outcomes of total hip replacement in patients with Down's syndrome.

Down's syndrome is associated with a number of musculoskeletal abnormalities, some of which predispose patients to early symptomatic arthritis of the hip. The purpose of the present study was to review the general and hip-specific factors potentially compromising total hip replacement (THR) in patients with Down's syndrome, as well as to summarise both the surgical techniques that may anticipate the potential adverse impact of these factors and the clinical results reported to date. A search of the literature was performed, and the findings further informed by the authors' clinical experience, as well as that of the hip replacement in Down Syndrome study group. The general factors identified include a high incidence of ligamentous laxity, as well as associated muscle hypotonia and gait abnormalities. Hip-specific factors include: a high incidence of hip dysplasia, as well as a number of other acetabular, femoral and combined femoroacetabular anatomical variations. Four studies encompassing 42 hips, which reported the clinical outcomes of THR in patients with Down's syndrome, were identified. All patients were successfully treated with standard acetabular and femoral components. The use of supplementary acetabular screw fixation to enhance component stability was frequently reported. The use of constrained liners to treat intra-operative instability occurred in eight hips. Survival rates of between 81% and 100% at a mean follow-up of 105 months (6 to 292) are encouraging. Overall, while THR in patients with Down's syndrome does present some unique challenges, the overall clinical results are good, providing these patients with reliable pain relief and good function.

Plastic cylindrical cement mold in the treatment of long bone metastatic fractures.

Presented here is a simple and practical surgical technique for creating a cement spacer in the cement-metal composite fixation of pathological fractures. This technique has been effectively used in several of our patients for fixation of pathological fractures due to metastatic disease of long bones.

Total hip replacement in patients with multiple epiphyseal dysplasia with a mean follow-up of 15 years and survival analysis.

The hip joint is commonly involved in multiple epiphyseal dysplasia and patients may require total hip replacement before the age of 30 years. We retrospectively reviewed nine patients (16 hips) from four families. The diagnosis of multiple epiphyseal dysplasia was based on a family history, genetic counselling, clinical features and radiological findings. The mean age at surgery was 32 years (17 to 63), with a mean follow-up of 15.9 years (5.5 to 24). Of the 16 hips, ten required revision at a mean of 12.5 years (5 to 15) consisting of complete revision of the acetabular component in three hips and isolated exchange of the liner in seven. No femoral component has loosened or required revision during the period of follow-up. With revision for any reason, the 15-year survival was only 11.4% (95% confidence interval 1.4 to 21.4). However, when considering revision of the acetabular shell in isolation the survival at ten years was 93.7% (95% confidence interval 87.7 to 99.7), reducing to 76.7% (95% confidence interval 87.7 to 98.7) at 15 and 20 years, respectively.

Total knee replacement with rotational proximal tibial osteotomy for osteoarthritis with severe external tibial torsion and patellar instability.

The management of osteoarthritis of the knee associated with patellar instability secondary to external tibial torsion > 45 degrees is challenging. Patellofemoral biomechanics in these patients cannot be achieved by intra-articular correction using standard techniques of total knee replacement. We reviewed seven patients (eight knees) with recurrent patellar dislocation and one with bilateral irreducible lateral dislocation who had undergone simultaneous total knee replacement and internal tibial derotational osteotomy. All had osteoarthritis and severe external tibial torsion. The mean follow-up was for 47.2 months (24 to 120). The mean objective and functional Knee Society scores improved significantly (p = 0.0001) from 29.7 and 41.5 pre-operatively to 71.4 and 73.5 post-operatively, respectively. In all patients the osteotomies healed and patellar stability was restored. Excessive external tibial torsion should be identified and corrected in patients with osteoarthritis and patellar instability. Simultaneous internal rotation osteotomy of the tibia and total knee replacement is a technically demanding but effective treatment for such patients.

Acetabular revision using an anti-protrusion (ilio-ischial) cage and trabecular metal acetabular component for severe acetabular bone loss associated with pelvic discontinuity.

Pelvic discontinuity with associated bone loss is a complex challenge in acetabular revision surgery. Reconstruction using ilio-ischial cages combined with trabecular metal acetabular components and morsellised bone (the component-cage technique) is a relatively new method of treatment. We reviewed a consecutive series of 26 cases of acetabular revision reconstructions in 24 patients with pelvic discontinuity who had been treated by the component-cage technique. The mean follow-up was 44.6 months (24 to 68). Failure was defined as migration of a component of > 5 mm. In 23 hips (88.5%) there was no clinical or radiological evidence of loosening at the last follow-up. The mean Harris hip score improved significantly from 46.6 points (29.5 to 68.5) to 76.6 points (55.5 to 92.0) at two years (p < 0.001). In three hips (11.5%) the construct had migrated at one year after operation. The complications included two dislocations, one infection and one partial palsy of the peroneal nerve. Our findings indicate that treatment of pelvic discontinuity using the component-cage construct is a reliable option.

Bilateral total hip replacement in osteogenesis imperfecta with hyperplastic callus.

Osteogenesis imperfecta is a rare inherited disorder of connective tissue which may present with recurrent fractures which are prone to nonunion and malunion resulting in deformity. Some patients develop osteoarthritis of the hip. Formation of hyperplastic callus after recurrent fractures may deform the shape of the femur and preclude the use of standard implants at joint replacement. Replacement can thus be technically demanding. We present a case of bilateral hip replacement in a patient with osteogenesis imperfecta and hyperplastic callus which was treated by the use of long femoral allografts and cemented femoral stems.