Fredrik af Ekenstam

Anatomical Studies on the Geometry and Stability of the Distal Radio Ulnar Joint

In fresh-frozen amputated- and cadaver arm specimens the anatomy and stability of the distal radio ulnar joint were investigated. The articulating surface of the sigmoid notch of the radius and the corresponding surface of the ulnar head facing the sigmoid notch were studied in transverse cryo sections. In each specimen the radius of the curvature of the sigmoid notch was 4-7 mm larger than that of the ulnar head and consequently pronation and supination are combined rotation-sliding movement in the distal radio ulnar joint. The radio ulnar ligament consists of a dorsal and a volar fibrous part, broadly attached to the distal rim of the sigmoid notch and converging towards the fovea of the ulnar head. The cartilaginous disc is centrally located between these fibrous strands. In neutral position the articulating surface of the sigmoid notch is optimally covering the articulating surface of the ulnar head. This contact area is gradually diminished during pronation-supination until only a marginal contact remains at the end of each movement. The distal radius is kept stable in pronation by the volar part and in supination by the dorsal part of the radio ulnar ligament.

Nonoperative compared with operative treatment of acute scaphoid fractures. A randomized clinical trial.

BACKGROUND Traditionally, acute nondisplaced scaphoid fractures have been treated nonoperatively in a cast, and the expected union rate approaches 90%. Internal fixation of nondisplaced scaphoid fractures has increased in popularity, and a union rate of 100% has been reported. The growing trend is to recommend internal fixation for the majority of acute scaphoid fractures. The true long-term benefits of this more complicated treatment modality have not yet been determined in randomized controlled trials. The purpose of this study was to compare the long-term results of operative fixation of acute scaphoid fractures with those of nonoperative treatment. METHODS During the period between 1992 and 1997, eighty-three patients with an acute nondisplaced or minimally displaced scaphoid fracture were randomly allocated to, and received, either nonoperative treatment with a cast or internal fixation with a Herbert screw. At a median of ten years after the injury, seventy-five (93%) of the eighty-one patients who were still alive were assessed clinically and radiographically. RESULTS All fractures united. A significant increase in the prevalence of osteoarthritis in the scaphotrapezial joint was found in the operatively treated group. No differences in subjective symptoms, as measured with limb-specific outcome scores, were found between the two groups. The range of motion and grip strength were greater, but not significantly greater, in the nonoperatively treated group. CONCLUSIONS This study did not demonstrate a true long-term benefit of internal fixation, compared with nonoperative treatment, for acute nondisplaced or minimally displaced scaphoid fractures. The long-term risks of surgery should be considered when recommending operative treatment.

The load on the radius and ulna in different positions of the wrist and forearm. A cadaver study.

Nine cadaver specimens were tested with load cells attached to both sides of an osteotomy of the distal radius and ulna. The load along the radius relative to the ulna could be measured in different positions of the wrist and forearm. There was less load along the radius in a position of wrist flexion, ulnar deviation and full forearm pronation.

Results from resection of the distal end of the ulna after fractures of the lower end of the radius.

Pain, impaired mobility and weakness in the wrist are common complications after fractures of the lower end of the radius. When these symptoms persist, resection of the distal end of the ulna has been the surgical treatment of choice. 24 patients who had undergone this procedure were reviewed. 50% stated they were not improved by the operation. Of 11 patients with degenerative changes in the distal radio-ulnar joint on preoperative X-ray, 8 stated they were helped by the operation, while of 13 patients without any signs of arthrosis in the distal radio-ulnar joint, only 4 experienced relief of their discomfort. A more discriminating approach to the treatment of the sequelae of fractures to the lower end of the radius is required. Resection of the distal end of the ulna is probably only indicated when the distal radio-ulnar joint shows sings of arthrosis.

Corrective Osteotomy of Malunited Fracture of the Distal end of the Radius

Thirty-nine patients with painful impaired forearm rotation and reduced grip strength after malunited fracture of the distal radius were treated with corrective osteotomy of the distal radius, bone grafting and internal fixation and followed for an average of 1.5 years. All patients stated that they were improved by the procedure. At follow-up 36 patients were graded as excellent or good, implying no pain, moderate limitation of motion and grip strength not less than 70% of the uninjured hand. Two patients were graded as fair and one as poor. It is concluded that surgical correction of the deformity is a good procedure when treating disabilities in the distal radio ulnar joint following malunited fractures of the distal end of the radius.

Triscaphoid arthrodesis and its complications

Carpal instability and/or arthrosis of the scaphotrapezial joint were treated with scaphotrapezio-trapezoid arthrodesis in 19 hands. Healing failed primarily in five hands as determined by conventional or computed tomography. No correlation was found to surgical methods or immobilization time. Surgical revision had to be done for four of the nonunions. These complications do not correspond to those described in the literature but draw attention to some adversities encountered in the use of this method.

Comparison of direct and indirect costs of internal fixation and cast treatment in acute scaphoid fractures: A randomized trial involving 52 patients

Background The most cost-effective treatment of scaphoid fractures has not yet been determined. Methods In a prospective trial, 52 employed or selfemployed patients with scaphoid fractures were randomized to closed (cast) or surgical treatment. Results There were 3 complications in the surgical group and 1 in the cast group. Median time off work was numerically but not statistically significantly greater after cast than after surgery (74/39 days). Manual workers (manuals) had a longer time away from work than non-manual employees/individuals who were selfemployed (non-manuals; median 84 days and 16 days, respectively; p < 0.001) and they had a longer time off work after cast than after surgery (median 100 days and 61 days; p = 0.03). Hospital costs were lower after cast than after surgery (p < 0.001). Work disability costs were numerically but not statistically significantly higher after cast than after surgery, and similarly, the total costs were lower after cast than after surgery. Work disability costs and total costs were higher in manuals than in non-manuals (p < 0.001). Non-manuals had lower total costs after cast than after surgery (p = 0.05). Interpretation There was a longer period of absence from work after cast than after surgery in manuals, but not in non-manuals. In non-manuals, total costs were lower after cast than after surgery. Socioeconomic classification had a greater influence on cost than mode of treatment.

Joint Cartilage Formation Induced by Silastic Sheet Spacer

In an experimental study in rabbits the effect on articular cartilage regeneration from subchondral bone induced by a temporary interposed silicone rubber sheet has been analyzed. The normal articular cartilage of the medial condyle of the femur was resected and the subchondral bone surface covered by a 2 mm thick Silastic sheet which was removed after 2 months. At that time cartilaginous tissue of a hyalin appearance was found to cover the resected surface. As early as one month after removal of the sheet this cartilage showed obvious signs of degeneration and a few months later no regenerating cartilage was left. It is concluded that in this study there is no experimental evidence supporting the idea that temporary interposition of a silicone rubber sheet is beneficial in the treatment of degenerative arthritis.

Entrapment of the metacarpophalangeal joint of the middle finger. Case report

Locking of the second metacarpal joint is common, but locking of other metacarpal joints is unusual. We present a case, in which the joint of the third finger locked and the mechanism was an osteophyte catching of the ulnar accessory collateral ligament. In such a case, the joint should be explored through a palmar approach. Conservative treatment is not recommended.

Closed Dislocation of the Scaphoid: A Case Report and Review of the Literature

A case of traumatic dislocation of the scaphoid bone treated by open reduction is reported. The bone remained vital, being nourished by a slender connection to the surrounding tissue. Experience from the few cases reported in the literature shows that closed reduction is often successful. If surgery is necessary it seems that it should be limited to simple reduction of the dislocation and that there is no need for primary arthrodesis or arthroplasty. Stable fixation is necessary to avoid re-dislocation and later wrist instability.