Pär Slätis

Operative Treatment of Severe Proximal Humeral Fractures

Results after the operative treatment of 41 severe proximal fractures of the humerus are reported. The fractures were classified according to Neer (1970a). The aim of treatment was accurate reduction and stable fixation of the fracture with screws or with screws and a plate. When scored according to Neers (1970a) functional assessment, results in the 31 patients re-examined more than 1 year postoperatively were excellent or satisfactory in 23 patients. Results were excellent or satisfactory in 14/15 patients with type III fractures, in 7/11 with IV, and 2/4 with type VI. In the only re-examined patient with a type V fracture the result was unsatisfactory. The most common technical error was a too high positioning of the AO plate and persistent varus deformation of the head of the humerus. High positioning of the plate caused post-operative restriction in the movements of the glenohumeral joint because the implant impinged under the acromion during abduction. No aseptic necrosis of the humeral head was observed. Of the patients of working age all but one returned to their preoperative occupations within a mean of 3.5 months after surgery.

Medial Dislocation of the Tendon of the Long Head of the Biceps Brachii

Medial displacement of the long tendon of the biceps brachii muscle is a rare condition associated with degenerative or traumatic ruptures of the rotator cuff. This condition was recorded in nine shoulders during 45 reconstructive procedures on the rotator cuff. Five of the displacements were complete, leaving the tendon medially displaced in a fascial sling; four were incomplete, allowing a to-and-fro medial displacement of the tendon out of the intertubercular groove. Anatomical dissections on eight shoulders showed that the coracohumeral ligament is the key ligament which keeps the biceps tendon aligned in the sulcus: transection of the medial part of the ligament allows the tendon to be medially displaced. There was no pathognomonic clinical sign of the luxation or subluxation. Since abnormal movement of the tendon in the sulcus may be an important cause of shoulder pain, the condition should be carefully looked for during reconstructive procedures on the rotator cuff. Tenodesis of the displaced tendon is recommended, either as the sole procedure or in combination with other reconstructive measures.

Costs and cost-effectiveness in hip and knee replacements. A prospective study.

The extensive benefits of the total hip (THA) and knee (TKA) replacements are well documented, but surprisingly little is known about their economics. We assessed costs, cost-effectiveness (C/E), and patient-related C/E variances in THA and TKA from data on 276 THA and 176 TKA patients. Patients with primary arthrosis, primary operation, and total joint replacement were recruited from seven hospitals between March 1991 and June 1992. Their use of health and other welfare services together with health-related quality of life (HRQoL) were measured before the surgery and at 6, 12, and 24 months postoperatively. HRQoL was assessed by the 15D, a 15-dimensional HRQoL instrument, and the Nottingham Health Profile. Costs were assessed from questionnaire responses, the Finnish Hospital Discharge Register, and Finnish Arthroplasty Register. Total hospital costs per patient were 45,000 FIM (US

Wear of the polyethylene acetabular cup. Metallic and ceramic heads compared in a hip simulator.

10,500) for THA and 49,600 FIM (US

Effect of rigid plate fixation on structure and mineral content of cortical bone.

11,500) for TKA. Prosthesis costs comprised 21% of these costs in THA and 24% in TKA. On average, hip patients gained more in terms of HRQoL, and the operations were more cost-effective. The C/E ratio for younger (< or = 60 years) knee patients did not differ from those in all age groups of hip patients, whereas TKAs in those over 60 years had a worse C/E ratio compared with all other patient subgroups. It was concluded that allocation efficiency can be improved by considering not only the intervention but also patient characteristics such as age. Indeed, the C/E ratio varied more across age groups of knee patients than between average THA and TKA patients.

External fixation of the pelvic girdle with a trapezoid compression frame

Ultra-high molecular weight polyethylene acetabular cups of 5 different total hip systems (Müller, Mallory-Head, Lubinus, P.C.A. and Charnley-Elite) were worn on a new 5-station hip joint simulator. The cups articulated against modular metallic (stainless steel in Müller and Charnley-Elite, ion-implanted Ti-6Al-4V in Mallory-Head, and Co-Cr-Mo in Lubinus and P.C.A.) and modular alumina ceramic femoral heads for 3 million walking cycles. The mean wear rate of cups against alumina heads (range 0-5.7 mg/10(6) cycles, corresponding to 0-0.008 mm/year) was usually lower than against metallic heads (range 3.9-178 mg/10(6) cycles, corresponding to 0.005-0.24 mm/year). In the metal-head prostheses, the mean wear rate was highest against stainless steel heads, and lowest against ion-implanted Ti-6Al-4V heads. As the wear rates are compared with published clinical observations, it can be concluded that the hip joint simulator is capable of producing realistic wear rates; it is a useful instrument in the study of the wear behavior of new designs, materials, surface treatments and coatings prior to clinical trials. However, the taper-fit attachment of modular heads proved problematical, showing corrosion and wear at the conical head-spigot interface.

Surgical repair of the rotator cuff and surrounding tissues. Factors influencing the results.

The effect of rigid plate fixation on the structure and mineral content of cortical bone were studied by light and fluorescence microscopy and by chemical analysis of calcium and hydroxyproline content in 27 rabbits from one day to 17 weeks after the attachment of a 5 hole ASIF-plate onto intact femur. Between the second and seventeenth postoperative weeks the plated cortical bone became progressively thinner and porotically transformed. Subendosteal resorption was partly offset by the formation of new subperiosteal bone that resulted in a slightly wider than normal, thin-walled tubular bone. At 17 weeks the mean calcium content of the tubular bone under the plate was 15% less than the initial postoperative content (p less than 0.05). The corresponding decrease in calcium content in the metaphyseal and epiphyseal areas of both the operated and the control bone was highly significant. The mean values for hydroxyproline in plated and control bones remained largely unchanged.

Dental bacteremia — a neglected cause of arthroplasty infections?: Three hip cases

The compression obtained with external anchorage in the anterior and posterior part of the pelvic girdle has been studied with a measuring device in the sacroiliac joint and and the symphysis of a specimen pelvis. Two models of external frames were tested, in both of which anchorage to the pelvic bone was brought about with 3 pins inserted in the iliac crests. The results were best with a trapezoid frame and bar exerting a compressive force on the pelvic girdle. When mounted with an inclination of 70 degrees to the long axis of the body, the frame exerted considerable compression on the posterior part of the pelvic girdle. This mounting afforded good stability of the detached hemipelvis. The trapezoid compression frame is recommended as an alternative to conventional methods of treating unstable fractures and dislocations of the pelvic girdle.

Registration of arthroplasties in Finland

The surgical pathology and clinical results of 78 reconstructions of chronic rotator cuff tears were reviewed retrospectively. The predominant complaint preoperatively was chronic pain with impaired shoulder function, resistant to repeated conservative treatment. Results according to a functional assessment were excellent or satisfactory in 71% of the patients, unsatisfactory in 12%, and failed in 17%. Relief of pain including night pain and pain with activity was obtained. Surgery should include a thorough exploration of the rotator cuff and the adjacent tissues. Accompanying problems, including biceps tendon disorders or impingement factors, must be recognized and treated at the time of the reconstruction procedure. Repair of the torn rotator cuff and treatment of concomitant lesions are effective operative procedures when symptoms are persistent and fail to respond to conservative treatment.

A Five-Station Hip Joint Simulator for Wear Rate Studies

We report on three patients with late hip replacement infection. The micro-organism was microaerophilic Streptococcus viridans, an oral organism, in all patients. Dental procedures had preceded the onset of the hip infection in all cases, and severe periodontal disease was observed on subsequent admissions.