Long-term survival of 2997 finger metacarpophalanageal joint arthroplasties from the Norwegian Arthroplasty Register.

We present the long-time survival of 2997 primary metacarpophalangeal (MCP) joint implants from the Norwegian Arthroplasty Register from 1994 to 2019. Six different implants were compared in terms of survival and risk of revision. The majority of implants were inserted in patients diagnosed with inflammatory diseases and in women. The overall survival was found to be 94%, 89%, 85% and 84% after 5, 10, 15 and 20 years. The most prevalent reason for revision was a fractured prosthetic component, and the second was pain. Implants inserted in the right hand and in younger patients had a higher risk for revision. Sex, type of implant, finger treated, one- or two-component prosthesis, and inflammatory or non-inflammatory conditions did not influence the survival. The frequency of MCP joint implantations decreased during the observation period. Our data show satisfactory long-term survival of the MCP implants, with no difference found between implant types or concepts.Level of evidence: II.

Cortical Plasticity After Surgical Tendon Transfer in Tetraplegics.

Background: Developmental cortical plasticity with reorganization of cerebral cortex, has been known to occur in young and adult animals after permanent, restricted elimination of afferent (visual or somatosensory) input. In animals, cortical representation of unaffected muscles or sensory areas has been shown to invade the neighboring cortex when this is deprived of its normal sensory input or motor functions. Some studies indicate that similar cortical plasticity may take place in adult humans. Methods: In patients with a high cervical spinal cord injury leaving the patient without any movements of the fingers, we performed fMRI studies of the cortical representation of an elbow flexor muscle before and after a surgical procedure that changed its function to a thumb flexor, thus providing the patient with a useful grip. Results: Preoperatively, the elbow flexion movement was elicited from a cortical area corresponding with the "elbow area" in healthy individuals. Despite the fact that an elbow flexor was used for the post-operative key-grip, this movement in the tetraplegic patients was elicited from a similar brain region as in healthy controls (the "hand area"). This supports our hypothesis that control of that muscle shifts from a brain region typically associated with elbow movement, to one typically associated with wrist movements. Conclusion: The findings presented here show with fMRI that the human cortex is capable of reorganizing itself spatially after a relatively acute change in the periphery.

Results of 189 wrist replacements. A report from the Norwegian Arthroplasty Register.

BACKGROUND AND PURPOSE: There is very little literature on the long-term outcome of wrist replacements. The Norwegian Arthroplasty Register has registered wrist replacements since 1994. We report on the total wrist replacements and their revision rates over a 16-year period. MATERIAL AND METHODS: 189 patients with 189 primary wrist replacements (90 Biax prostheses (80 of which were cementless), 23 cementless Elos prostheses, and 76 cementless Gibbon prostheses), operated during the period 1994-2009 were identified in the Norwegian Arthroplasty Register. Prosthesis survival was analyzed using Cox regression analyses. The 3 implant designs were compared and time trends were analyzed. RESULTS: The 5-year survival was 78% (95% CI: 70-85) and the 10-year survival was 71% (CI: 59-80). Prosthesis survival was 85% (CI: 78-93) at 5 years for the Biax prosthesis, 77% (CI: 30-90) at 4 years for the Gibbon prosthesis, and 57% (CI: 33-81) at 5 years for the Elos prosthesis. There was no statistically significant influence of age, diagnosis, or year of operation on the risk of revision, but females had a higher revision rate than males (RR = 3, CI: 1-7). The number of wrist replacements performed due to osteoarthritis increased with time, but no such change was apparent for inflammatory arthritis. INTERPRETATION: The survival of the total wrist arthroplasties studied was similar to that in other studies of wrist arthroplasties, but it was still not as good as that for most total knee and hip arthroplasties. However, a failed wrist arthroplasty still leaves the option of a well-functioning arthrodesis.

Osteoporosis as a risk factor for distal radial fractures: a case-control study.

BACKGROUND: Distal radial fractures occur earlier in life than hip and spinal fractures and may be the first sign of osteoporosis. The aims of this case-control study were to compare the prevalence of osteopenia and osteoporosis between female and male patients with low-energy distal radial fractures and matched controls and to investigate whether observed differences in bone mineral density between patients and controls could be explained by potential confounders. METHODS: Six hundred and sixty-four female and eighty-five male patients who sustained a distal radial fracture, and 554 female and fifty-four male controls, were included in the study. All distal radial fractures were radiographically confirmed. Bone mineral density was assessed with use of dual x-ray absorptiometry at the femoral neck, total hip (femoral neck, trochanter, and intertrochanteric area), and lumbar spine (L2-L4). A self-administered questionnaire provided information on health and lifestyle factors. RESULTS: The prevalence of osteoporosis was 34% in female patients and 10% in female controls. The corresponding values were 17% in male patients and 13% in male controls. In the age group of fifty to fifty-nine years, 18% of female patients and 5% of female controls had osteoporosis. In the age group of sixty to sixty-nine years, the corresponding values were 25% and 7%, respectively. In adjusted conditional logistic regression analyses, osteopenia and osteoporosis were significantly associated with distal radial fractures in women. Osteoporosis was significantly associated with distal radial fractures in men. CONCLUSIONS: The prevalence of osteoporosis in patients with distal radial fractures is high compared with that in control subjects, and osteoporosis is a risk factor for distal radial fractures in both women and men. Thus, patients of both sexes with an age of fifty years or older who have a distal radial fracture should be evaluated with bone densitometry for the possible treatment of osteoporosis.

Vitamin D inadequacy is associated with low-energy distal radius fractures: a case-control study.

INTRODUCTION: Vitamin D inadequacy is associated with hip fractures, but the relationship has not been explored for distal radius fractures. AIMS: To compare serum 25-hydroxyvitamin D (s-25(OH)D) status in low-energy distal radius fracture patients and a group of matched controls, and examine whether observed differences in s-25(OH)D between patients and controls would remain after adjusting for bone mineral density (BMD), body mass index (BMI), and smoking history. METHODS: A total of 575 female and 72 male low-energy distal radius fracture patients (50-90 years) and 534 female and 52 male matched controls were included. The primary measure was levels of vitamin D. Secondary measures were BMD assessed by dual energy X-ray absorptiometry, BMI and smoking history. RESULTS: Mean s-25(OH)D was 66.5nmol/L in female patients and 78.7nmol/L in controls (p<0.001). The corresponding figures in men were 64.5 and 77.0nmol/L (p=0.017). In adjusted conditional logistic regression analyzes, s-25(OH)D <50nmol/L (OR=2.32, 95% CI: 1.47-3.64, p<0.001), and 50-75 (OR=1.70, 95% CI: 1.17-2.47, p=0.005) were associated with distal radius fractures in women. s-25(OH)D <50nmol/L (OR=6.27, 95% CI: 1.17-33.66, p=0.032) was associated with distal radius fractures in men. CONCLUSIONS: Vitamin D inadequacy is associated with low-energy distal radius fractures in both women and men. Differences in vitamin D levels are independent of BMD, BMI or smoking history.

Dynamic compared with static external fixation of unstable fractures of the distal part of the radius: a prospective, randomized multicenter study.

BACKGROUND: External fixation is an established method of treating certain types of distal radial fractures. We have designed a dynamic external fixator to treat these fractures. The purpose of the present study was to compare this device with current static bridging external fixators in terms of anatomical and functional results. METHODS: We conducted a prospective randomized study to compare the radiographic and clinical results of dynamic external fixation with those of static external fixation for the treatment of seventy unstable distal radial fractures. Mobilization of the wrist was begun in the dynamic fixator group on the day after surgery. The external fixation frames were kept in place for a mean of six weeks. The patients were assessed clinically and radiographically at the time of removal of the fixator and at three, six, and twelve months. RESULTS: Dynamic fixation resulted in a significantly better restoration of radial length at all follow-up visits in comparison with static fixation. There were no significant differences in radial tilt or radial inclination between the two groups. Wrist flexion, radial deviation, and pronation-supination were regained significantly faster in the dynamic fixator group. Wrist extension was significantly better in the dynamic fixator group in comparison with the static fixator group at all follow-up times. Self-evaluation with use of the Disabilities of the Arm, Shoulder and Hand score and a visual analog pain score demonstrated no significant differences between the two groups at the time of the latest follow-up. Superficial pin-track infections were significantly more common in the dynamic external fixator group than in the static fixator group. CONCLUSIONS: Continuous dynamic traction with a dynamic external fixator compares favorably with the use of static external fixators for the treatment of unstable fractures of the distal part of the radius.

Different osteosyntheses for Colles' fracture: a mechanical study in 42 cadaver bones.

BACKGROUND AND PURPOSE: In recent years several different plate designs for internal fixation of fractures of the distal radius have been developed. However, few biomechanical studies have been performed to compare these new implants. The purpose of this study was to compare the mechanical properties of 5 different commercially available plates (3 volar and 2 dorsal) with standard K-wire fixation using a distal radial cadaver model. MATERIAL AND METHODS: 42 human radial bones from 26 cadavers were included. The bone mineral density (BMD) was measured by DEXA in all bones, and the radial bones were assigned to 6 equiv alent groups based on bone density and total amount of mineral. A distal radial osteotomy was done and a dorsal 30-degree wedge of bone was removed. 1 K-wire fixation group and 5 plate groups were tested for rigidity, yield load, and maximum load. RESULTS: When data from dorsally and volarly applied plates were pooled, we did not find any statistically significant differences between them regarding stiffness, yield load, and maximum load. The K-wire group showed significantly lower yield load than 3 of the plate groups. There were no statistically significant differences in yield load between the 5 plate groups. The K-wire group showed lower rigidity than the plate groups. The K-wire group and 1 plate group failed at a statistically significant lower maximum load than the 4 other plate groups. INTERPRETATION: The volar plates had the same mechanical stability as the dorsally applied plates, and they are therefore a good alternative to dorsally applied plates. K-wire osteosynthesis was inferior to plate osteosyntheses regarding all mechanical properties.

External fixation of fractures of the distal radius: a randomized comparison of the Hoffman compact II non-bridging fixator and the Dynawrist fixator in 75 patients followed for 1 year.

BACKGROUND AND PURPOSE: External fixators allowing movement during fracture healing are commonly used for treatment of unstable distal radius fractures. The dynamic Dynawrist fixator with the distal pins in metacarpal bone may avoid fixation problems in comminuted fractures and may reduce the risk of nerve injury. We compared anatomical and functional outcome for the well-established Hoffmann compact II non-bridging fixator and for the Dynawrist fixator. PATIENTS AND METHODS: 75 patients with unstable distal radius fractures were randomized to treatment with either the Hoffman compact II fixator (the H-group) or the Dynawrist fixator (the D-group). Anatomical and functional variables were recorded preoperatively, postoperatively, and at 6, 12, 24, and 52 weeks. Pain was assessed using the VAS score and function was assessed using DASH score. RESULTS: Postoperatively, radial tilt, inclination, and radial length all improved statistically significantly in both groups. At time of removal of the fixators, the H group had superior volar radial tilt. At the 52-week follow-up, there were no statistically significant differences between the groups regarding anatomical variables. At 6 weeks, flexion was greater in the D group but at 12, 24, and 52 weeks flexion was similar in the two groups, as were the other wrist and forearm movements. There were no statistically significant differences between the groups according to VAS and DASH scores. 3 nerve injuries occurred in the H group and 1 in the D group (p = 0.4), all of which were transient. INTERPRETATION: The Dynawrist bridging but dynamic fixator gives radiographic and functional outcome similar to that of the Hoffman II compact non-bridging fixator.

[Dr. Nicolaes Tulp's anatomy lecture]. / Dr. Nicolaes Tulps anatomiforelesning.

"The Anatomy Lesson of Dr. Nicolaes Tulp" (1632) is one of Rembrandt's most famous paintings. It is often regarded as simply a group portrait of the Surgeons' Guild in Amsterdam at the time. Some inconsistencies in the perspective, the size and anatomy of the dissected arm, and the doctor's slightly awkward hand pose, have been put down to Rembrandt's lack of experience and ignorance of anatomy. However, from a surgeon's point of view there are clear indications that Rembrandt fully understood Dr Tulp's lecture and has captured in his painting an accurate demonstration of the functional anatomy of the superficial flexors of the fingers.

Displaced paediatric fractures of the distal radius.

INTRODUCTION: The purpose of this study was to review, over a fixed period of time and in a geographically defined area, all paediatric fractures of the distal radius that were initially reduced. We wished to assess the fracture pattern at different ages, the seasonal variation, the severity of the initial angulation, and the radiological outcome in terms of reangulation, remodelling, refracture, growth disturbance, and functional outcome. MATERIALS AND METHODS: A total of 88 patients were followed in a prospective setting (11 fractures of the distal radial physis). The pre- and post-reduction and follow-up radiological variables were measured. Patients with significant malangulation at union were re-examined after 7 years to assess the degree of spontaneous remodelling. RESULTS: The mean malangulation before reduction was 19 degrees , after reduction 5 degrees and at union 4 degrees . Eight patients had secondary displacement during the casting period. Fractures with more than 15 degrees of malangulation at union had completely remodelled and had normal function at final follow-up. CONCLUSION: Conservative treatment may still be regarded as the gold standard for closed paediatric fractures of the distal radius. In the present series, the remodelling capacity was excellent.

Corrective osteotomy for malunited extra-articular fractures of the distal radius: a follow-up study of 33 patients.

We present a series of 33 consecutive patients treated with lengthening osteotomy due to malunited extra-articular fractures of the distal radius. Thirty-one patients were able for long-term follow-up a median (range) of seven (2-20) years after the procedure. The indication for reconstruction was mainly impaired function of the wrist. Both the anatomy and function were improved significantly postoperatively. The median radial length improved 5 mm, the radial tilt 25 degrees, and the radial inclination improved 9 degrees. The median improvement of forearm supination was 20 degrees, pronation 10 degrees, dorsal wrist flexion 10 degrees, and volar flexion 20 degrees. Twenty-two of 29 patients (76%) rated the functional results as good or excellent. The functional results were significantly better postoperatively, but the results were still better on the uninjured side. The grip strength on the operated hand was 82% of the uninjured hand, and the median postoperative DASH-score was 21. In five patients the graft resorbed (one fracture of the plate) and needed reoperation. All eventually healed and the anatomical and functional results were good. Another patient had symptomatic osteoarthrosis and later had a full wrist fusion. We conclude that every effort should be made to prevent malunion in the treatment of distal radius fractures, becauseeven after anatomical correction, function is not restored fully in all patients.

Experience with the AO Pi-plate for displaced intra-articular fractures of the distal radius.

We have used open reduction and internal fixation (ORIF) with the AO pi-plate in 32 displaced, intra-articular fractures of the distal radius. The indication was a displaced intra-articular fracture with a step-off of more than 1 mm and a gap between fragments of more than 3 mm, judged from the primary computed tomograms (CT). All fractures were classified as AO type C3. Twenty-nine patients were followed-up after a mean of 23 (9-46) months. The dorsal tilt, the radial length, the radial inclination, the articular step-off, and the intra-articular gap between fragments were substantially improved postoperatively. All the patients had excellent or good extra-articular and intra-articular alignment. Two patients had reduced extension power of the first finger. Seventeen patients had Disability of the arm, shoulder, and hand (DASH) scores of less than 10 points, five had scores between 11 and 20, three between 21 and 30, three between 31 and 40, and one patient had a score of 65 points. Complications occurred in two patients: one had a painful amputation neuroma of the superficial radial nerve, and one developed adhesions of the flexor tendons of the second and third fingers because the screws were too long and had penetrated the tendon sheaths. We conclude that the AO pi-plate is an excellent option for the most comminuted fractures of the distal radius.