PubMed Health⌕ Search

Biomedical subjects

David Ring

Publications and source records attributed to David Ring.

At least 37 records · Page 2Linked to original sources
PubMed2006

Malunion and nonunion of the metacarpals and phalanges.

The management of nonunion and malunion in the metacarpals and phalanges is influenced by the multiple gliding structures and the propensity for stiffness, the ability of adjacent digits to substitute functionally for compromised digits, the small size of the bones, and associated complications. Amputation and arthrodesis are useful treatment options for nonunions in the hand because they are nearly always atrophic, are frequently associated with joint stiffness and tendon adhesions, and often occur in digits with poor nerve function, vascularity, or skin cover. Surgical fixation with autogenous bone grafts and stable internal fixation has a high union rate with resultant restoration of alignment and stability, but achieves modest improvements in motion. Slightly larger implants than one would use for a fracture at the same size and structural (corticocancellous) bone grafts are useful for obtaining adequate stability to initiate immediate exercises in order to limit the potential for stiffness. Malunion is treated only when doing so offers useful functional advantages. The optimal timing and site of intervention are debatable; however, it is usually easiest to restore alignment when operating at the site of the original fracture and prior to complete consolidation of the fracture. This is particularly true for articular fractures. Once these fractures are mature, it may be preferable to perform an extra-articular osteotomy. If a late intra-articular osteotomy is performed, it should be done in such a way as to create large fragments that are easier to repair and more likely to retain their blood supply.

Finger Phalanges↗
PubMed2005

Compass hinge fixator for acute and chronic instability of the elbow.

OBJECTIVE: To maintain concentric reduction of an unstable elbow and to allow active exercises after the treatment of complex elbow injuries or their sequelae. INDICATIONS: Recurrent dislocation or subluxation of the elbow after repair or reconstruction of bony, capsuloligamentous, and/or musculotendinous stabilizers. Tenuous fixation of large coronoid fractures due to fragmentation or osteopenia. Stabilization of the joint after fascial arthroplasty or debridement for infection, if the debridement destabilizes the elbow. Relative indication: maintenance of range of motion after release of contractures. CONTRAINDICATIONS: Absent patient compliance. Lack of familiarity of surgeon with elbow anatomy and function as well as with hinged external fixation techniques. SURGICAL TECHNIQUE: Preferably posterior longitudinal midline incision. Placement of axis pin in the center of rotation of the distal humerus. Application of the fixator over this wire. Placement of Schanz screws into humerus und ulna taking care to protect the radial and ulnar nerves. Removal of axis pin. Rechecking of entire frame and tightening. RESULTS: The authors' experience with the Compass Hinge Fixator documents restoration of stability and excellent motion after relocation of a chronic simple elbow dislocation, a useful role in reconstructing acute and chronic elbow instability after fracture-dislocation, and a limited role in restoring mobility after severe contracture release.

Acute Disease↗
PubMed2005

Nonunion of the distal radius.

Distal radius nonunion is either more common or more commonly recognized. The success of operative treatment to gain union seems to have improved along with improvements in operative fixation of fractures of the distal radius. Operative treatment to gain union or arthrodese the wrist can improve function and comfort with relatively few complications.

Arthrodesis↗
PubMed2005

Retrograde (volar) scaphoid screw insertion-a quantitative computed tomographic analysis.

PURPOSE: The benefit of placing the screw tip in the center of the proximal pole of the scaphoid is supported by clinical and biomechanical data. In this investigation we attempted to quantify guidelines for optimal screw insertion into the scaphoid through a volar percutaneous approach using measurements from computed tomography images. METHODS: The parameters of safe insertion of a 3.0-mm cannulated-headed screw (Synthes, Paoli, PA) using a volar (retrograde) insertion technique were measured using quantitative computer analysis of computed tomography images of 15 unfractured scaphoids. In the coronal plane the average screw length for the most radial, most ulnar, and intermediate paths for safe screw insertion and the radial clearance of the trapezium were measured. In the sagittal planes defined by these screw paths the length of the screw, the length and depth of the concavity on the volar surface of the scaphoid, and the distance between a line corresponding to the center of the screw path and the volar surface of the trapezium were measured. RESULTS: Significant differences (1-way analysis of variance) were measured for the average screw lengths for different screw insertion paths in both the coronal and sagittal planes (with the shortest screw lengths observed for the most ulnar starting points) and for the volar clearance of the trapezium, which was greater for a radial screw path. The intermediate screw path-a measure of optimal screw insertion-passed radial to the radial edge of the trapezium in 10 of 15 patients (67%) with an average clearance of 3.9 mm (range, 1.1-7.9 mm) in those patients. The depth of the concavity on the volar surface of the scaphoid averaged 1.6, 2.0, and 2.5 mm in the 3 sagittal planes. CONCLUSIONS: Screw fixation of the scaphoid through a volar approach is hindered by the trapezium, risks cutout through the concavity in the volar surface of the scaphoid, and is most likely to violate the dorsoulnar aspect of the radiocarpal articular surface of the scaphoid if the screw is too long. A relatively radial starting point facilitates placement of the screw tip in the center of the proximal pole and helps avoid the trapezium but drilling or partial excision of the trapezium often may be necessary for optimal screw placement.

Adolescent↗
PubMed2005

Both scanning plane and observer affect measurements of scaphoid deformity.

PURPOSE: The influence of angular deformity of the scaphoid on wrist function and arthrosis is debated and the reliability of the described quantitative measurements of deformity has been questioned. We hypothesized that the inherent imprecision with which computed tomography scanning planes are selected introduces another source of variability in measurements of scaphoid deformity, further diminishing their reliability. METHODS: Sagittal plane images of 15 computed tomograms of normal scaphoids were evaluated in 3 different reconstruction planes. Four observers measured the lateral intrascaphoid angle, the dorsal cortical angle, and the height-to-length ratio of the 45 images in random order and then measured them again in a distinct random order 2 weeks later. The variability of each observer's measurements (intraobserver reliability) was evaluated with Pearson correlation coefficients. The agreement of the measurements made by the 4 observers (interobserver reliability) and the agreement of the measurements of the same bone in different reconstruction planes (interplane reliability) were evaluated using interclass correlation coefficients. RESULTS: The intraobserver reliability was poor for 27 of 36 comparisons. The interobserver reliability of the dorsal cortical angle and the intrascaphoid angle was poor for all reconstruction planes. The interobserver reliability of the height-to-length ratio was good for 2 planes and poor for the third plane. The interplane reliability was poor for 7 of 12 comparisons, with no single measurement technique remaining consistent for all observers across reconstruction planes. CONCLUSIONS: Quantitative measurements of scaphoid deformity have very limited reliability for individual observers, between different observers, and depending on the plane in which the image of the scaphoid is produced. Even the most reliable measure of deformity (height-to-length ratio) was not consistent between reconstruction planes. Unless more reliable scanning and measurement techniques are developed ideas about the effect of scaphoid deformity on wrist function will remain to a large degree speculative.

Adolescent↗
PubMed2005

Health status after total wrist arthrodesis for posttraumatic arthritis.

PURPOSE: Total wrist arthrodesis is regarded as the most predictable way to relieve the pain of posttraumatic wrist arthritis. Wrist arthrodesis also is believed to be compatible with a high level of upper-extremity function. This study evaluated the effect of total wrist arthrodesis on both general and upper-extremity-specific health status in patients treated for posttraumatic wrist arthritis. METHODS: By using an institutional review board-approved protocol 22 patients were evaluated an average of 6 years after total wrist arthrodesis for posttraumatic arthritis. Upper-extremity-specific and general health status were measured using the Disabilities of the Arm, Shoulder, and Hand questionnaire and the Short-Form 36 (SF-36) instruments, respectively. Patient satisfaction and interest in pursuing a wrist-mobilizing procedure should one become available also were assessed. Objective assessment included grip strength, digit range of motion, and radiographic fusion. RESULTS: Grip strength averaged 79% of the uninvolved wrist. The average Disabilities of the Arm, Shoulder, and Hand questionnaire score was 25. The average physical component score of the Short-Form 36 was 39 and the average mental component score was 52. Fourteen patients complained of wrist pain, including severe pain in 4 patients. Fifteen patients were satisfied or very satisfied with the result of the fusion, 5 patients were neutral, and 2 patients were mildly dissatisfied. Twenty patients would elect to have a procedure that could make their wrist move again if one were available. CONCLUSIONS: Substantial dysfunction was noted on both upper-extremity-specific and general health status measures after total wrist arthrodesis for posttraumatic conditions. Pain was improved but not eliminated.

Adult↗
PubMed2005

Treatment of the neglected distal radius fracture.

Operative treatment of inadequately or imperfectly treated fractures of the distal radius can improve wrist and hand function substantially, but rarely restores the limb to normal. Patients with malunion of the distal radius present either with poor radiographic alignment before complete healing of the fracture (nascent malunion) or with functional problems that may be related to inadequate alignment of a healed fracture (mature malunion). Corrective osteotomy is offered to patients who have sufficient malalignment that the surgeon thinks problems are inevitable or to patients in whom the functional deficit can be related clearly to the malunion. Ununited fractures are associated with painful instability of the wrist and very poor hand function. Operative treatment has proved successful even when the distal fragment is small. Operative treatment for reconstruction of the distal radius has been facilitated by the introduction of plates with angular stable screws (screws that lock into the plate). Painful arthritis is salvaged with arthrodesis.

Arthritis↗
PubMed2005

Comminuted diaphyseal fractures of the radius and ulna: does bone grafting affect nonunion rate?

BACKGROUND: The recommendation of Anderson and colleagues to bone graft even relatively minor amounts of comminution (a third of the bone diameter) in the treatment of diaphyseal forearm fractures with plate-and-screw fixation has been questioned. This study examines factors related to nonunion in adult patients with comminuted diaphyseal fractures of both the radius and the ulna to determine the relative influence of bone grafting. METHODS: Over a 15-year period at two hospitals, 41 patients with diaphyseal fractures of both forearm bones satisfied the following criteria: comminution (Orthopaedic Trauma Association grade IV or higher) of at least one fracture; treatment with 3.5- or 4.5-mm dynamic compression plates at least six holes in length; and minimum 12-month follow-up. Multiple logistic regression was used to determine the contribution of the following factors to the risk of nonunion: multiple injuries; ipsilateral upper extremity injury; open wound; and the application of cancellous bone graft at the fracture site. RESULTS: Five patients had nonunion of one or both bones (12%). According to the multiple logistic regression model, none of the factors studied had a statistically significant association with nonunion (p > 0.40 for all). The odds ratios were as follows: multiple injuries, 2.1 (95% confidence interval [CI], 0.34-12.9); ipsilateral injury, 0.68 (95% CI, 0.058-7.84); open fracture, 1.46 (95% CI, 0.21-9.89); and bone graft, 0.98 (95% CI, 0.15-6.42). CONCLUSION: Nonunion occurred in 12% of comminuted, diaphyseal fractures of both bones of the forearm treated with dynamic compression plates. No single factor was associated with nonunion. In particular, the use of bone graft was not associated with a higher rate of union.

Adolescent↗
PubMed2005

Psychological factors associated with idiopathic arm pain.

BACKGROUND: Psychological and personality factors may be as important as, or more important than, pathological processes in the experience of pain, particularly in patients whose pain has a vague or uncertain source. METHODS: Validated measures of psychological factors were used to prospectively evaluate fifty-six patients with a single, discrete pain complaint and fifty-one patients with vague, diffuse idiopathic arm pain. Pain was assessed with use of 10-point Likert scales, the Pain Anxiety Symptoms Scale, the Pain Catastrophizing Scale, the Wahler Physical Symptom Inventory, the Body Consciousness Questionnaire, and the Multidimensional Health Locus of Control Scale. RESULTS: Patients with idiopathic arm pain reported more severe pain at rest (p = 0.02) and with repeated movements (p = 0.01); exhibited higher levels of cognitive anxiety (p = 0.008); demonstrated greater helplessness (p = 0.002), pain magnification (p = 0.007), and overall catastrophic coping mechanisms for dealing with pain (p = 0.005); and showed a tendency for increased somatic complaining (p = 0.07). A multiple logistic regression model identified the total score on the Pain Catastrophizing Scale as the sole predictor of idiopathic pain complaints. CONCLUSIONS: Pain complaints without a clear physical cause are common and are frustrating for both patients and physicians. Awareness of the psychological factors associated with idiopathic arm pain may lead to more effective interventions designed to improve coping mechanisms while at the same time limiting the use of meddlesome and potentially harmful diagnoses and treatments.

Adaptation, Psychological↗
PubMed2005

Revision of unstable capitellocondylar (unlinked) total elbow replacement.

BACKGROUND: Instability is a recognized complication associated with unlinked total elbow implants. The best form of treatment of this problem is uncertain as very little has been written about it. METHODS: Twelve patients underwent operative treatment of instability at the site of a capitellocondylar unlinked total elbow replacement, and the results were reviewed retrospectively. The study group included ten women and two men with an average age of fifty-eight years. Ten patients had rheumatoid arthritis. Three elbows underwent conversion to a semi-constrained hinged prosthesis. In the other nine elbows, an attempt was made to continue with an unlinked prosthesis: three had reconstruction of one or both collateral ligaments, four had component revision, and two had both ligament reconstruction and component revision. RESULTS: After an average duration of follow-up of six years (range, two to fifteen years) only three patients had retained a functioning unlinked prosthesis. Of the remaining nine patients, three had had a conversion to a semi-constrained arthroplasty at the time of the index procedure, four had had a conversion to a semi-constrained prosthesis at the time of a salvage procedure, one had had a resection arthroplasty, and one had a painfully dislocated elbow and had declined revision. Thus, seven elbows eventually underwent conversion to a semi-constrained prosthesis; these conversion procedures were technically difficult, with perforation of the humerus occurring in six patients and perforation of the ulna occurring in four. After all procedures, the average elbow flexion was 132 degrees and the average flexion contracture was 25 degrees. According to the Mayo Elbow Performance Index, there were four excellent results, three good results, three fair results, and one poor result. CONCLUSIONS: Revision of an unlinked total elbow prosthesis to a linked total elbow prosthesis is difficult, but it restores elbow function. Although the present series documents the unpredictability of attempts to salvage an unstable unlinked prosthesis, it seems reasonable to attempt at least one soft-tissue procedure before converting to a linked prosthesis.

Aged↗
PubMed2005

Hinged elbow external fixation for severe elbow contracture.

BACKGROUND: When it was first introduced, it was hoped that hinged external fixation with a built-in gear mechanism for applying passive motion and static progressive stretch by turning a dial would improve the arc of ulnohumeral motion, by gradually stretching contracted muscles, after open release of a severe elbow contracture. METHODS: Forty-two patients were evaluated at an average of thirty-nine months after operative release of a severe posttraumatic elbow contracture (defined as < or =40 degrees of motion). Twenty-three patients had been treated, during the early part of the study, with a hinged external fixator that incorporated a worm gear to apply static progressive stretch postoperatively. These patients were compared with nineteen patients who had been treated without hinged external fixation during the later part of the study, when the hinge was used less frequently. The operative techniques did not otherwise change during the study period. Demographic and injury characteristics as well as associated problems were comparable between the two groups. RESULTS: The average gain in the range of motion after the index procedure was 89 degrees in the patients treated with a hinge and 78 degrees in those treated without a hinge, an insignificant difference with the numbers available (p = 0.175). Complications associated with use of the hinge included five pin-track infections, one case of pin-track osteomyelitis, one ulnar fracture through a pin site, two broken Schanz screws, and two cases of irritation of the ulnar nerve. CONCLUSIONS: Open release of a severe elbow contracture results in a substantial gain in motion, with or without hinged elbow fixation. The slightly greater improvement in motion provided by the hinge does not justify the associated increase in risk, expense, and complications.

Adolescent↗
PubMed2005

Corrective osteotomy for intra-articular malunion of the distal part of the radius.

BACKGROUND: Corrective osteotomy is an appealing treatment for malunited articular fractures of the distal part of the radius since articular incongruity may be the factor most strongly associated with arthrosis and diminished function after such fractures. Enthusiasm for osteotomy has been limited by concerns regarding the difficulty of the technique and the potential for additional injury, osteonecrosis, and nonunion. METHODS: Twenty-three skeletally mature patients were evaluated at an average of thirty-eight months after corrective osteotomy for an intra-articular malunion of the distal part of the radius. The indication for the osteotomy included dorsal or volar subluxation of the radiocarpal joint in fourteen patients and articular incongruity of > or =2 mm as measured on a posteroanterior radiograph in seventeen patients. Six patients had combined intra-articular and extra-articular malunion. The average interval from the injury to the osteotomy was six months. The average maximum step-off or gap of the articular surface prior to the operation was 4 mm. RESULTS: One patient had a subsequent partial wrist arthrodesis because of radiocarpal arthrosis, and three patients had additional surgery because of dysfunction of the distal radioulnar joint. One patient had a rupture of the extensor pollicis longus, which was treated with a tendon transfer. The final articular incongruity averaged 0.4 mm, and the final grip strength averaged 85% of that on the contralateral side. The rate of excellent or good results was 83% according to the rating systems of Fernandez and of Gartland and Werley, and 43% according to a modification of the rating system of Green and O'Brien. CONCLUSIONS: The results of corrective osteotomy for the treatment of intra-articular malunion are comparable with those of osteotomy for the treatment of extra-articular malunion. Intra-articular osteotomy can be performed with acceptable safety and efficacy, it improves wrist function, and it may help to limit the need for salvage procedures such as partial or total wrist arthrodesis.

Adolescent↗
PubMed2005

Pain dominates measurements of elbow function and health status.

BACKGROUND: Elbow function can be quantified with use of physician-based elbow-rating systems and health status questionnaires. Our hypothesis was that pain has a strong influence on these scores, which overwhelms the influence of objective factors such as motion. METHODS: One hundred and four patients were evaluated, at a minimum of six months (average, forty-six months) after the latest surgery for an intra-articular fracture of the elbow, with use of three physician-based evaluation instruments (Mayo Elbow Performance Index [MEPI], Broberg and Morrey rating system, and American Shoulder and Elbow Surgeons Elbow Evaluation Instrument [ASES]), an upper-extremity-specific health status questionnaire (Disabilities of the Arm, Shoulder and Hand [DASH]), and a general health status questionnaire (Short Form-36 [SF-36]). Multivariate analysis of variance and regression modeling were used to identify the factors that account for the variability in scores derived with these measures-in other words, which factors have the strongest influence on the final score. RESULTS: Pain alone accounted for 66% of the variability in the MEPI scores, 59% of the variability in the Broberg and Morrey scores, and 57% of the variability in the ASES scores. Models that included other factors accounted for only slightly more variability (73%, 79%, and 79%, respectively), and those that did not include pain accounted for only 22%, 41%, and 41% of the variability. Thirty-six percent of the variability in the DASH scores could be accounted for by pain alone, and 45% could be accounted for by pain and range of motion. Models not including pain accounted for only 17% of the variability in the DASH scores. CONCLUSIONS: Pain has a very strong influence on both physician-rated and patient-rated quantitative measures of elbow function. Consequently, these measures may be strongly influenced by the psychosocial aspects of illness that have a strong relationship with pain, and objective measures of elbow function such as mobility may be undervalued. It may be advisable to evaluate pain separately from objective measures of elbow function in physician-based elbow ratings.

Adult↗
PubMed2005

Prevalence of osteoarthrosis of the trapeziometacarpal joint.

BACKGROUND: The age and gender-related prevalence of arthrosis of the trapeziometacarpal joint has been incompletely defined. METHODS: The radiographs of 615 consecutive patients who had presented with an isolated fracture of the distal part of the radius over a two-year period were evaluated for evidence of trapeziometacarpal arthrosis. We used a simple three-grade rating system suitable for standard wrist radiographs. Grade I indicated no or nearly no arthrosis; grade II, obvious arthrosis; and grade III, a totally destroyed joint. This rating system was demonstrated to have adequate intraobserver reliability (average kappa of 0.72, p < 0.001) and interobserver reliability (average kappa of 0.56, p < 0.001). The number of patients with each grade of arthrosis was analyzed according to age and gender. RESULTS: The overall radiographic prevalence of trapeziometacarpal arthrosis in patients with a distal radial fracture increased steadily from the age of forty-one years onward and reached a prevalence of 91% in patients older than eighty years of age. The prevalence increased more rapidly in women than in men; it reached 94% in women who were older than eighty years of age compared with 85% in men who were older than eighty years of age. The prevalence of grade-III trapeziometacarpal arthrosis (a totally destroyed joint) was much greater in women than in men at all age levels; it reached a prevalence of 66% in women older than eighty years of age compared with 23% in men older than eighty years of age. CONCLUSIONS: The radiographic prevalence of trapeziometacarpal arthrosis in patients presenting for treatment of a distal radial fracture is age-related, and trapeziometacarpal arthrosis is more likely to lead to complete joint destruction in women than it is in men.

Adolescent↗
PubMed2005

Combined dorsal and volar plate fixation of complex fractures of the distal part of the radius.

BACKGROUND: Fractures of the distal part of the radius that are associated with complex comminution of both the articular surface and the metaphysis (subgroup C3.2 according to the Comprehensive Classification of Fractures) are a challenge for surgeons using standard operative techniques. METHODS: Twenty-five patients with subgroup-C3.2 fractures that had been treated with combined dorsal and volar plate fixation were evaluated at an average of twenty-six months after the injury. Subsequent procedures included implant removal in twenty-one patients and reconstruction of a ruptured tendon in two patients. RESULTS: An average of 54 degrees of extension, 51 degrees of flexion, 79 degrees of pronation, and 74 degrees of supination were achieved. The grip strength in the involved limb was an average of 78% of that in the contralateral limb. The average radiographic measurements were 2 degrees of dorsal angulation, 21 degrees of ulnar inclination, 0.8 mm of positive ulnar variance, and 0.7 mm of articular incongruity. Seven patients had radiographic signs of arthrosis during the follow-up period. A good or excellent functional result was achieved for twenty-four patients (96%) according to the rating system of Gartland and Werley and for ten patients (40%) according to the more stringent modified system of Green and O'Brien. CONCLUSIONS: Combined dorsal and volar plate fixation of the distal part of the radius can achieve a stable, mobile wrist in patients with very complex fractures. The results are limited by the severity of the injury and may deteriorate with longer follow-up. A second operation for implant removal is common, and there is a small risk of tendon-related complications.

Bone Plates↗
PubMed2005

Management of distal humerus fractures.

Fractures of the distal humerus are complex injuries that can be effectively treated with open reduction and internal fixation (ORiF). Exposure of a complex intra-articular fracture may best be achieved through a posterior approach with osteotomy of the olecranon process. The ulnar nerve must be identified and protected, the articular surface must be reduced anatomically, and rigid fixation must be applied to both the medial and lateral columns of the distal humerus. Range of motion should be initiated as soon as possible postoperatively. Complications such as ulnar neuropathy, elbow stiffness, heterotopic ossification, and nonunion should be treated aggressively. Total elbow arthroplasty represents an effective option for fractures that cannot be treated with ORIF.

Fracture Fixation, Internal↗