Colles' fractures: functional treatment in supination

PURPOSE OF THE STUDY

Abraham Colles classified and described fractures of the distal epiphyseal radius. He recommended the arm should be immobilized in a cast that extends from the base of the fingers to above the elbow, while holding this joint at ninety degrees of flexion the forearm in pronation and the wrist in slight flexion and ulnar deviation. We identified the brachioradialis muscle as the main culprit in the frequently observed loss of reduction of the fracture. Since the brachioradialis is attached to the distal region of the radius and functions as a flexor of the elbow when the forearm is in pronation, its stimulation easily displaces a reduced fracture, particularly if its geometry suggests axial instability. We concluded that post-reduction stabilization in supination was more desirable than in pronation.

MATERIAL AND METHODS

Prospective study of one hundred and fifty-six patients suffering from Colles' fractures who were treated with the functional method. Approximately one-half of the fractures were immobilized in pronation and the other half in supination. The median age of the patients was 49 years. After approximately eleven days of immobilization in an above-the-elbow cast that held the forearm in a relaxed attitude of supination and the wrist in slight flexion and ulnar deviation, a new cast or brace was applied. The appliance permitted flexion of the elbow and slightly limited extension. We utilized modified Lindstom criteria to assess radiological results, according to types of fractures and by groups treated in supination and pronation.

RESULTS

In the type I and III (non-displaced) fracture series there appeared to be no significant difference in the functional results between the pronation and supination treated groups. In the type II category, in the supinated fractures, there were 9 excellent, 4 good and no fair or poor results. In the pronated group 9 excellent, 8 good and one fair result. The functional results in type IV fractures treated in supination were excellent in 11 instances, good in 7 and fair in 2. In fractures treated in pronation there were 5 excellent, 10 good and 5 fair results. There were no poor results in either group. 85% of type II fractures and 85% of type IV fractures treated in supination had excellent or good results. In the pronation group, 67% had excellent or good results in type II and 40% in type IV classification. In combining the results for all types of braced Colles' fractures, (I-IV) 93% of the supination group and 87% of the pronation group achieved excellent or good functional results. In analyzing overall results regardless of type of fracture or position of immobilization, 90% of the patients had excellent or good results.

CONCLUSION

We treated Colles' fractures in supination and compared the results with those obtained when treated in pronation. The results indicated a lower incidence of re-displacement in the supination group. We developed a forearm brace that permits flexion of the elbow, but prevented pronation of the forearm, and limited extension of the elbow in approximately the last fifteen degrees. It permits minimally limited flexion of the wrist but prevents wrist dorsiflexion. It makes impossible any radial deviation. The place of surgery in the management of Colles' fractures should be limited to those fractures that when treated by non-surgical means are not likely to render satisfactory functional and cosmetic results. There is not at this time a consensus as to when to use the surgical approach. The complication rate from the surgery have not clearly identify superiority of one over the other. Nonetheless, the surgical treatment has a definite place in the armamentarium of the orthopaedic surgeon. In a number of situations, it is the treatment of choice.

A surgical technique for the prevention of femoral lysis in cement total hip arthroplasty

Femoral bone lysis in total hip arthroplasty is thought to be primarily due to polyethylene or metal debris arising from the femoral or acetabular components. The debris appears to gradually seep into the cement/ bone interface, eventually generating the chemical reaction that produces lysis.We experimented with a surgical technique that attempts to construct a proximal bony barrier preventing migration of debris. Following the injection of the acrylic cement and the insertion of the femoral component, but prior to complete polymerization of the cement, bone chips are pressed over the cement, in contact with the viable femoral cortex. The bone chips become rigidly fixed; probably regain viability from the femoral cortex, and seal the proximal femur. In this manner, debris cannot travel into the femoral canal. Although we do not have anatomical evidence that a viable bony seal has formed the absence of lysis and bone/cement radiolucent lines over a period of time ranging from three to fourteen years suggests the permanent presence of a physiological barrier. Attempts to identify the permanency of the bony seal by means of CT scans proved inconclusive. Key words: total hips, lysis, femoral lysis, cortical graft.

Functional treatment of closed segmental fractures of the tibia

PURPOSE OF THE STUDY Segmental tibial fractures are commonly believed to be more difficult to manage, requiring surgical treatment. Our experience with forty-eight segmental tibial fractures suggests that these fractures, if closed and with shortening of an acceptable initial degree and a corrected deformity, may be successfully treated with functional braces. MATERIAL AND METHODS Forty-eight closed segmental fractures of the tibia that had initial shortening .12 mm and angular deformity manually corrected to .7 degrees were stabilized in an above-the-knee cast for a median time of 33 days and a mode of 15 days. They were subsequently stabilized in a functional brace that allowed unencumbered motion of all joints. All other segmental fractures outside the established parameters were managed by other methods. RESULTS All fractures healed at a median time of 15.3 weeks. The final shortening was 4.7 millimeters with a mode of 12 millimeters. The maximum shortening was 14 millimeters. Fractures healed with a medial-lateral (M.L) angular deformities ranging zero to 19 degrees, a median of 5.9 degrees and a mode of 3.4 degrees. CONCLUSION The relatively early introduction of weight bearing and the freedom of motion of all joints that the brace permits seem to result in motion at the fracture site, which in turn enhances osteogenesis. As we have previously documented, the initial shortening that closed tibial fractures experience does not increase with the physiological use of the extremity. The final shortening and angulation observed in most of the fractures should not be considered complications, simply inconsequential deviations from the normal. The same should apply to closed segmental fractures.

[Humeral diaphyseal fractures: functional bracing]

Functional bracing of humeral diaphyseal fractures was conceived after initial experiences with a similar method was used in the management of diaphyseal tibial fractures. Over the years, tibial functional bracing underwent major evolutionary changes, and found its indications basically limited to a smaller group of fractures, consisting of closed, axially unstable fractures that experience at the time of the injury an acceptable degree of shortening, and to transverse fracture that are appropriately reduced and rendered stable. On the other hand, functional bracing of diaphyseal humeral fractures has, maintained the initial indications, contraindications and methodology. This article describes the concept, indications and contraindications of functional bracing of humeral diaphyseal fractures and provides results of 620 fractures with complete follow-up. In 97.5% of the patients, the average healing time was 11.5 weeks. 16 patients (2.5%) required operative intervention because of a nonunion and 4 patients (<1 degrees) of the patient had a refracture after brace removal. Nerve function did not return in only one of the 67 patient who had radial nerve palsy.

A radiographic review of 135 total hip Charnley arthroplasties followed between 15 and 35 years

The long-term radiologically interpreted results of low-friction Charnley hip arthroplasties have been previously suggested to be influenced by surgical details, such as orientation of the femoral component, degree of coverage of the plastic acetabulum and other features. We carefully analyzed the radiographs of 135 Charnley arthroplasties that had remained functional, had not been revised and had follow-ups between 15 and 35 years. Several common denominators were identified amongst these radiographs: 93.5% arthroplasties had 100% coverage of the acetabular component; 88% had acetabular inclination between 40-45 degrees ; 84.5% had a proximal/medial column of cement between 3 and 5 millimeters at the level of femoral head resection; 81% had a femoral canal/stem ratio more than 50%; and 84% had a column of cement that extended below the tip of the prosthesis. This study supports the importance of technical surgical details that enhance the chances of long-term survival of cemented total hip arthroplasties.

[Mobility of unstable fractures of the odontoid during helmet removal. A biomechanical study]

In severe motorcyclist accidents unstable injuries of the cervical spine can usually not be excluded before an X-ray has been taken in the hospital. Despite this the helmet has to be taken off at the place of the accident in order to provide adequate treatment and airway management of the injured driver. There are no data in the current literature showing what happens to unstable lesions of the cervical spine during helmet removal. An experimental unstable lesion of the cervical spine was created by an osteotomy of the odontoid in 10 fresh frozen cadavers with intact soft tissues. All motions occurring in the segments C1-2 and C2-3 during helmet removal were recorded by fluoroscopy. The average motion in the unstable segment C1-2 was 23.7 degrees during a full range of extension-flexion movement of the cervical spine without any signs of dislocation of the segment. After application of the helmet there was one case of dislocation of C1-2 in neutral supine position already, and two further cases of dislocations during helmet removal. The average motion of C1-2 recorded during helmet removal was 19.0 degrees (2-25 degrees ), median 18.0 degrees. In order to avoid fracture dislocations and motion in the unstable upper cervical spine the helmet should better be cut in pieces at the place of the accident. There is a need for discussions with helmet producers to develop a new generation of helmets that can be removed easily without manipulating the head.

A new modular testing system for biomechanical evaluation of tibial intramedullary fixation devices

This biomechanical study was performed to evaluate a new modular, tibial testing system developed for analysis of tibial nails and their locking screws.A new testing system, consisting of five modules, was designed to simulate a tibia. For this study one module was removed to simulate a 55-mm distal tibial defect inducing maximum loading on the distal portion of the implant and locking bolts. The tibial load offsets were 23 mm proximally and 10 mm distally medial to the centreline of the tibial shaft to simulate the location of the expected resultant load during the peak loading and inversion torque on the ankle during the gait cycle. Four solid tibial nails (STN, Stryker-Howmedica-Osteonics, Kiel, Germany) were tested to static failure and 15 nails were tested dynamically. Our results showed that the solid tibial nails fractured in the testing device in the same manner and location as they do in clinical series. Evaluation of the results showed the mean fatigue limit of the STN to be 1.4 kN for 500,000 cycles with a standard deviation (S.D.) of 0.33 kN. This biomechanical study establishes a standard technique for the biomechanical testing of tibial nails, in a clinically relevant manner, avoiding the inconsistency of cadaver bone tests. As it is a standardised test set-up this new modular testing system could serve as a standard by which small diameter tibial nails and other devices could be evaluated and compared with other systems currently in use.

Triangulated pedicle screw construct technique and pull-out strength of conical and cylindrical screws

To compare the mechanical effectiveness of a new conical screw design with a conventional cylindrical screw design, the screw insertion time, torque, and pull-out strength of single-pedicle screw and triangulated-pedicle screw constructs of each type of screw were compared in human cadaveric vertebral bodies. The time required to insert the conical screws was less than that required for cylindrical screws. Regression analysis revealed a positive correlation between insertion torque and pull-out strength of single and triangulated constructs of each type of screw. The conical screw had a greater increase than the cylindrical screw in the pull-out strength of triangulated pedicle screw constructs. Application of the new conical screw design was significantly faster, and the new screw had better mechanical fixation to the vertebral body than did the conventional cylindrical screw tested.

The Stabilizing Effects of Different Orthoses in the Intact and Unstable Upper Cervical Spine: A Cadaver Study

BACKGROUND

Although cervical orthoses are frequently used in prehospital stabilization and in the definitive treatment for lesions of the cervical spine, there is little information about the control of extension-flexion, lateral bending, and rotation given to individual segments by different designs.

METHODS

In an experimental in vitro study with four fresh frozen cadavers, the halo vest was compared with the soft collar, prefabricated Minerva brace, and Miami J collar. The controlling effects for the segments C1-2 and C2-3 were tested for all four devices in the intact and the unstable spine with an Anderson type II fracture of the odontoid.

RESULTS

All four orthoses reduced the range of motion at both C1-2 and C2-3 of the intact spine significantly, although none of the three semirigid devices provided a halo-like immobilization in the intact spine. The osteotomy of the odontoid increased the range of motion in the segment C1-2. The soft collar did not give any clinically relevant stability to the unstable spine. Miami J and Minerva brace provided a similar moderate control in the sagittal plane but a much better control of "torque" in the upper cervical spine. The halo vest did not allow any measurable motion in any plane with our experimental external loading.

CONCLUSION

The halo vest seems to be the first choice for conservative treatment of unstable injuries of the upper cervical spine, although pin track problems, accurate fitting of the vest, and a lack of patient compliance lead to clinical failures.

Functional bracing for the treatment of fractures of the humeral diaphysis

BACKGROUND

Nonoperatively treated fractures of the humeral diaphysis have a high rate of union with good functional results. However, there are clinical situations in which operative treatment is more appropriate, and, though interest in plate osteosynthesis has decreased, intramedullary nailing has gained popularity in recent years. We report the results of treating fractures of the humeral diaphysis with a prefabricated brace that permits full motion of all joints and progressive use of the injured extremity.

METHODS

Between 1978 and 1990, 922 patients who had a fracture of the humeral diaphysis were treated with a prefabricated brace that permitted motion of adjacent joints. The injured extremities were initially stabilized in an above-the-elbow cast or a coaptation splint for an average of nine days (range, zero to thirty-five days) prior to the application of the prefabricated brace. Orthopaedic residents, supervised by teaching staff, provided follow-up care in a special outpatient clinic. Radiographs were made at each follow-up visit until the fracture healed.

RESULTS

We were able to follow 620 (67 percent) of the 922 patients. Four hundred and sixty-five (75 percent) of the fractures were closed, and 155 (25 percent) were open. Nine patients (6 percent) who had an open fracture and seven (less than 2 percent) who had a closed fracture had a nonunion after bracing. In 87 percent of the 565 patients for whom anteroposterior radiographs were available, the fracture healed in less than 16 degrees of varus angulation, and in 81 percent of the 546 for whom lateral radiographs were available, it healed in less than 16 degrees of anterior angulation. At the time of brace removal, 98 percent of the patients had limitation of shoulder motion of 25 degrees or less. We were unable to follow most of the patients long-term, as they did not return to the clinic once the fracture had united and use of the brace had been discontinued.

CONCLUSIONS

Functional bracing for the treatment of fractures of the humeral diaphysis is associated with a high rate of union, particularly when used for closed fractures. The residual angular deformities are usually functionally and aesthetically acceptable. The present study illustrates the difficulties encountered in carrying out long-term follow-up of indigent patients treated in charity hospitals that are affiliated with teaching institutions. These difficulties are also becoming common with patients insured under managed-care organizations and are frequent in our peripatetic population.

Functional fracture bracing

Functional bracing is an effective therapeutic modality in the management of selected fractures of the tibia, humerus, and ulna, particularly low-energy injuries. In the case of tibial fractures, it is applicable only to reduced transverse fractures and to axially unstable fractures with an acceptable degree of shortening. The rate of union of tibial fractures after functional bracing is approximately 97%. The initial shortening noted with closed tibial fractures rarely increases with weight bearing. Shortening has been reported to be as little as 12 mm in 95% of patients, with angulation of 8 degrees in 90%. Such minimal shortening and angulation do not affect functional results. In closed and type I open diaphyseal humeral fractures treated with functional braces, the nonunion rate is approximately 3%. Most of the reported residual angular deformities have been functionally and cosmetically acceptable. For isolated ulnar fractures, the nonunion rate is approximately 2%. Functional fracture bracing is predicated on the premise that motion at the fracture site encourages osteogenesis. The method is applicable only to selected fractures, and it is necessary to have a clear understanding of its rationale, indications, and technique.

Biomechanics of a less invasive procedure for reconstruction of the ulnar collateral ligament of the elbow

A reconstruction of the anterior bundle of the ulnar collateral ligament of the elbow using bone anchors was compared regarding strain and valgus load strength with the intact ulnar collateral ligament and the reconstructed ulnar collateral ligament using bone tunnels. In both normal and reconstructed elbows, the anterior band and posterior band were tight during only a portion of the range of motion. Toward extension, the mean peak strain in the anterior band was tight for the normal and bone anchor groups, but lax in the bone tunnel group. Toward extension, the mean peak strain in the posterior band was lax in all elbows. Toward flexion, the strain in the anterior band was lax in the normal and bone anchor groups, but tight in the bone tunnel group. The mean of the peak strains for the posterior band toward flexion was tight for all elbows. Mean valgus load strength of normal elbows was 22.7 +/- 9.0 N.m. The bone tunnel and bone anchor mean strengths were 76.3% and 63.5%, respectively, of normal elbow strength. We concluded that the bone anchor reproduced the normal anatomy and mechanical function of the ulnar collateral ligament more closely than the bone tunnel, and that both reconstruction methods were significantly weaker than the normal ulnar collateral ligament. However, we found no significant difference in reconstruction strength between bone anchor and bone tunnel.

Isolated ulnar shaft fractures treated with functional braces

OBJECTIVE

To report the results from functional bracing of isolated ulnar shaft fractures.

DESIGN

Retrospective review.

SETTING

Two university hospitals.

PATIENTS

Isolated ulnar shaft fractures in 444 patients were stabilized in functional braces that permitted full range of motion of all joints.

INTERVENTION

Prefabricated braces that extended from below the elbow to above the wrist were applied within the first week after the initial injury.

OUTCOME MEASURES

Union of the fracture, fracture angulation, and final range of motion of the forearm were evaluated.

RESULTS

Two hundred eighty-seven patients were available for follow-up (65 percent). Union took place in 99 percent of the fractures. Shortening of the ulna averaged 1.1 millimeters (range 0 to 10 millimeters). Final radial angulation averaged 5 degrees (range 0 to 18 degrees). Dorsal angulation averaged 5 degrees (range 0 to 20 degrees). Average loss of pronation was greatest in fractures of the proximal third of the ulna, averaging 12 degrees. Fractures in the distal third averaged a loss of 5 degrees of pronation.

CONCLUSIONS

Functional bracing is a viable therapeutic alternative in the management of isolated ulnar shaft fractures. It is associated with a 99 percent union rate and good to excellent functional results in more than 96 percent of patients.

Effect of nonsteroidal antiinflammatory drugs on fracture healing: a laboratory study in rats

We studied the effects of two nonsteroidal antiinflammatory drugs (NSAIDs) on fracture healing in rats: ibuprofen (30 mg/kg/day) and indomethacin (1 mg/kg/day). Femoral fractures were induced via a three-point bending technique. NSAIDs were administered orally for 4 or 12 weeks. Control animals received no medication. In each group a minimum of six animals were killed at the following intervals: 2, 4, 6, 8, 10, and 12 weeks postfracture. Fracture healing was determined by mechanical testing and histologic evaluation. The bending strength of each fractured femur was expressed as a percentage of the strength of the intact, contralateral femur. Histologic evaluation was performed on serial longitudinal sections stained with hematoxylin and eosin using a qualitative score of maturity of the callus. Ibuprofen and indomethacin both retarded fracture healing, with significant differences in "mechanical healing" found between the control and experimental groups after 10 weeks of drug administration. Both drugs also induced qualitative histologic changes manifested by delayed maturation of callus, which was noticeable earlier than the difference found by mechanical testing of bone. Our data suggest that NSAIDs have an inhibitory effect on fracture repair that is reversible after cessation of indomethacin but not ibuprofen.

Fracture healing and mast cells

We analyzed the morphology and localization of mast cells during the course of fracture repair in control rats and in animals with delayed healing of fractures induced by nonsteroidal antiinflammatory drugs (NSAIDs). In the first 2 weeks of fracture healing in control animals, mast cells were found either in the vicinity of blood vessels or in the vascularized tissue proliferating into the cartilaginous portion of subperiosteal callus. In the later stages (6-8 weeks), mast cells were seen in loose connective tissue in bone marrow surrounded with translucent ground substance. At this stage of healing, a hyperplasia of mast cells and cell degranulation was often seen in close proximity to osteoclasts and areas of bone resorption. Treatment with NSAIDs delayed fracture healing and the appearance of mast cell hyperplasia in bone marrow for approximately 4 weeks, suggesting that mast cells have specifically defined temporal and regional distribution during the process of bone repair. Histochemical studies documented a significant amount of chymase in the mast cells in callus. This enzyme was purified from mast cells by chromatography and was able to digest in vitro proteins extracted from bone. Our data suggest that mast cells in fracture healing are involved in digestion of extracellular matrix in callus tissue that could facilitate (a) angiogenesis in the early stages of healing, and (b) the replacement of provisional tissue with newly formed bone in the later stages of fracture healing.

A biomechanical evaluation of magnetic resonance imaging-compatible wire in cervical spine fixation

In a bovine cervical spine model, the ultimate and fatigue strengths as well as relative magnetic resonance imaging artifact produced by titanium, cobalt chrome, and stainless-steel wires in various gauges were assessed. Single-cycle and fatigue strength of wire constructs were measured. Although larger wires generally had greater static strength, fatigue strength was mixed. Sixteen-gauge titanium, and all stainless-steel models (22-gauge braided, 18-gauge, and Songer cable) withstood 10,000 cycles without failure, whereas all other constructs rarely could withstand a similar 10,000 cycles. Magnetic resonance imaging was performed on calf cervical spines instrumented with the various materials. Titanium exhibited the least artifact, stainless-steel showed the greatest artifact, and cobalt chrome an intermediate amount. Although titanium wire produces the least amount of magnetic resonance imaging artifact, it remains a poor choice for implant fixation because its notch sensitivity reduces its fatigue resistance compared with stainless steel, which remains the more dependable choice.

Precision oblique osteotomy for shortening of the ulna

The obstacles of prolonged healing time and technically demanding osteotomy and plate fixation in the performance of ulnar shortening osteotomies have been overcome by a precision system that includes a 45 degrees osteotomy and 2.7 mm interfragmentary lag screw. In 23 transverse osteotomies healing time averaged 21 weeks with one nonunion. In 17 precision oblique osteotomies healing time averaged a substantially shorter 11 weeks. Biomechanical data obtained from cadaveric testing comparing these two constructs demonstrated a structural stiffness that was clearly greater in torsion testing for the oblique osteotomy. No biomechanical difference was identified in the anteroposterior and lateral bending tests. The system permits the reliable performance of two parallel osteotomy cuts, allowing the removal of a precise amount of bone. The compression device and specialized plate permit easy coaptation of the osteotomy surfaces, which are locked into position by a precise 22 degrees interfragmentary lag screw. The surgical procedure is more quickly completed, and the frustration of this previously challenging procedure is now completely removed.

Sliding characteristics of compression hip screws in the intertrochanteric fracture: a clinical study

Sliding of compression hip screws (CHS) is advantageous when it allows for controlled collapse of a hip fracture and progressive stabilization. A retrospective review was performed on 47 intertrochanteric (IT) fractures treated with a Zimmer CHS. Previous studies had identified certain parameters as being important to CHS sliding characteristics in vitro. Using conventional diagnostic material (radiographs), we sought to use these parameters as clinically useful tools. Screw sliding, as well as geometric parameters of CHS that relate to screw sliding, such as barrel engagement in relation to screw extension and screw-plate angle, were measured and calculated from serial radiographs. Almost all screw sliding occurred within 30 days postoperation. Fracture stability and quality of reduction were two main factors relating to screw sliding (p < 0.01). High screw-plate angle and longer screw-barrel engagement had no correlation with screw sliding even in unstable fractures. All five failures were due to cut-out after complete or almost complete collapse of the sliding mechanism in non-anatomically reduced fractures in osteoporotic females. Unstable fractures in osteoporotic bone do seem to require supplementary fixation beyond sliding screw fixation alone. None of the mechanical parameters (as judged from plane radiographs) that control the tendency of the CHS to slide could be statistically correlated with incidence or degree of sliding. Therefore, it was concluded that it is impractical to attempt to predict sliding tendency from plane radiograph measurements.

Tibial fracture stability. Analysis of external fracture immobilization in anatomic specimens in casts and braces

Plaster casts, custom-fabricated fracture braces, and prefabricated fracture braces were compared in the laboratory for the stability they provided to closed, experimental, diaphyseal fractures of the tibia and fibula on anatomic specimens. The stability was comparable for each type of device tested for the loading conditions of isolated compression, bending, and torsion. Length stability (overriding at the fracture site) was poor, rotation was marginal (by clinical standards), and angulation was very good. Selective removal of portions of each cast and brace demonstrated that the classic patellar-tendon-bearing (PTB) extension proximally and below ankle extensions distally had insignificant effects on stability of these middle-third diaphyseal fractures for the conditions tested. The soft-tissue compression provided by a snug, tapered "cylindrical" sleeve, which encompassed the soft tissues from the tibial tubercle to the flare of the distal tibia and fibula, provided the stabilizing effect for all of the devices tested.

Diaphyseal fractures of the humerus. Treatment with prefabricated braces

Using a prefabricated brace, we treated 233 patients who had a fracture of the humeral shaft. One hundred and seventy patients were available for follow-up, which ranged from five weeks to forty-eight months. In these patients (forty-three open and 127 closed fractures), the average time to union was 10.6 weeks; the average varus-valgus angulation, 5 degrees; the average anterior-posterior angulation, 3 degrees; and the average shortening, as measured radiographically, four millimeters. All but three of the patients had an excellent or a good functional result with a nearly full range of motion of the extremity. There were a minimum of complications, including three non-unions. Because of the low morbidity and high rate of success, we concluded that the treatment of choice for diaphyseal fractures of the humerus is the prefabricated brace.

Treatment of isolated ulnar shaft fractures with prefabricated functional fracture braces

In a prospective study, from September 1980 to December 1984, 146 isolated ulnar shaft fractures were treated with prefabricated fracture braces. Clinical and roentgenographic follow-up data were available for 73 fractures. Functional results were rated excellent in 64 fractures (88%), good in seven (9%), and poor in two (3%). All fractures healed in an average time of 57 days. The mean angulation measured 6 degrees in the mediolateral plane and 4 degrees in the anteroposterior plane. The complication rate was 18%, relating mostly to residual angulation. Most isolated fractures of the distal one-half of the ulnar shaft can be treated successfully with prefabricated fracture braces.

Conservative management of difficult phalangeal fractures

Stable fractures of the metacarpal and proximal phalanges can be treated satisfactorily by closed methods. The problem in those unstable fractures is whether to treat with open or closed reduction. Stiffness of the proximal interphalangeal joint (PIP), malunion, rotation deformities, shortening, and nonunion are known complications of fractures of the proximal phalanx. Fractures at the base of the proximal phalanx. Fractures at the base of the proximal phalanx have low incidence of complications if they are treated closed. Fractures at the shaft carry a much larger risk of complications with either type of treatment. This study of 158 fractures of the proximal phalanx demonstrates that there is a place for conservative treatment in the management of unstable shaft fractures of the proximal phalanx.

Abductor muscle performance in total hip arthroplasty with and without trochanteric osteotomy. Radiographic and mechanical analyses

Total hip arthroplasty was performed for unilateral hip disease in 26 patients with trochanteric osteotomy (TS) and 27 patients without osteotomy (NS). Early postoperative recovery of function, pain, mobility, radiographic changes, and abduction torques were recorded and evaluated. Theoretic analysis of hip mechanics based on radiographic measurements was compared with measured abduction torques for each patient. Function, pain, and mobility ratings were similar for both groups pre- and postoperation. Radiographic measurements demonstrated better mechanical reconstruction of hips in both groups. There was a trend, but no statistically significant correlation, of mechanical parameters and measured isokinetic or isometric abduction torques at the hip joint in the TS group. In the NS group, no correlation was found between mechanical parameters and measured torques. A significant improvement in recovery of torque was found in the NS group when compared to the TS patients.

Healing of fractures with freeze-dried cortical bone plates. Comparison with compression plating

The healing of fractures of the radius with internal fixation by stainless-steel compression plates was compared with fractures fixed with freeze-dried bone-plate allografts. Fractures fixed with metallic plates gained slightly less than half the biomechanical strength of the contralateral control bone and healed without noticeable external callus formation. Bone-plated fractures regained three-fourths of the biomechanical strength of controls and healed by forming an external callus. Bone-plate allografts were eventually incorporated in the host bone. Allograft plates were vascularized and remodeled into cancellous bone in the process of incorporation in the host bones.

The effects of function in fracture healing and stability

A mechanically based classification system and hypothesis for fracture healing with peripheral callus has been proposed based on many years of clinical experience and numerous laboratory research studies. This hypothesis describes the interactions and influences on fracture healing from the vascular, mechanical, electric, chemical, and thermal environments in specific callus regions surrounding the fracture site. The central theme to this phenomenon is motion at the fracture site. The single factor distinguishing the effects of closed functional bracing of fractures from all other treatment modalities is motion between the fragments which results from early functional activity. Perhaps the stimulus to a prolonged inflammatory response is provided by friction between moving fracture fragments and the surrounding tissues. An increased vascular response results, and environmental factors are stimulated to form an abundant peripheral callus. Three distinct callus zones exist which provide overlapping stages of healing based on structure and optimized physiologic conditions. Clinical signs and symptoms, such as fracture stability as well as motion and pain at the fracture site, combine to provide the optimum feedback mechanism to control functional activity, which in turn governs environmental factors. Roentgenographic appearance can be better judged for mechanical significance if these three callus regions are appreciated. In animals as well as in humans, if function has correctly influenced the environment during callus formation, refracture strength is often greater than that of the original bone.

Histopathology and metallurgical analysis of a removed Lane plate at 53 years postimplantation: a case report

A vanadium steel Lane plate with nickel coating and low grade steel screws were removed from a patient 53 years postimplantation. Corrosion of the parts was extreme, but the reaction in the surrounding tissues was surprisingly quiescent under the circumstances. By today's standards, the materials, their application, and their performance were totally unacceptable. However, the biological system tolerated this "insult" well.

A quantitative comparative analysis of fracture healing under the influence of compression plating vs. closed weight-bearing treatment

The study compared the healing of fractures treated with rigid immobilization with the healing of fractures without internal fixation. Comparative studies were made of the cytologic, morphologic and mechanical properties of callus from closed fractures in 2 groups of dogs: one plated, the other not. Significant differences were observed in the 2 groups in early stages of healing. The biomechanical differences between the 2 groups persisted into later stages of healing, even after histologic and electron microscopic appearance of cellular activity and new bone formation had become similar. In general, closed, nondisplaced fractures of dogs' radii treated without surgical procedures and followed by early functional activity demonstrated a cytologically more active endosteal callus and increased biomechanical strength characteristics at the fracture site.

Factors contributing to lysis of the femoral neck in total hip arthroplasty

A radiographic analysis of 483 Charnley total hip arthroplasties performed from July 1970 to November 1975 demonstrated that 13% of the hips had lysis of the medial femoral neck. The findings suggest that the lysis of the medial femoral neck is significantly reduced if the femoral stem is oriented in a valgus or neutral position and with at least 5 mm of cement separating the stem of the prosthesis and the medial cortex of the femoral neck.

Fracutres of the proximal tibia and tibial condyles: a clinical and laboratory comparative study

Angulatory deformities frequently develop following condylar and proximal diaphyseal tibial fractures. Laboratory studies conducted in cadaver specimens with artificially created fractures closely resembled the behavior of fractures treated with functional braces. Providing that the fibula factor is properly assessed, selected condylar and proximal tibial shaft fractures can be successfully treated by nonsurgical means including early knee motion in a brace followed by graduated weight-bearing ambulation.

Clinical experiences with a titanium alloy total hip prosthesis: a posterior approach

Using a titanium alloy femoral prosthesis (STH Zimmer) and an ultra high molecular weight polyethylene acetabular cup with a posterior surgical approach to the hip joint, 237 consecutive total hip arthroplasties in 215 patients were performed between December 1975 and May 1977. The preliminary results and early postoperative complications suggest that this system can be considered an alternative to total hip arthroplasty using other materials and surgical approaches.

Fracture healing in rat femora as affected by functional weight-bearing

Femoral fractures were created in rats to determine whether there were differences in healing under conditions of immobilization and under conditions of immediate weight-bearing. Histological and roentgenographic differences were present by the second week after fracture and differences in mechanical properties were also present. These differences became progressively greater during the next three weeks. Functional weight-bearing was found to accelerate the rate of fracture healing and to improve significantly the strength of the healing bone.