Molecular detection of Wolbachia pipientis in natural populations of sandfly vectors of Leishmania infantum in endemic areas: first detection in Lutzomyia longipalpis.

A polymerase chain reaction-based method was used to screen sandflies for infection with Wolbachia (Rickettsiales: Rickettsiaceae), an intracellular bacterial endosymbiont found in many arthropods and filarial hosts. Positive results were obtained in five of 200 field-collected sandflies and were confirmed by sequencing. All sandflies were Lutzomyia longipalpis (Diptera: Psychodidae) captured in a region endemic for visceral leishmaniasis in Brazil. This is the first study to identify Wolbachia infection in this Lutzomyia species, which is the main vector of leishmaniasis in the study area. The low infection rate found in this study (2.5%), together with the lack of detection of Wolbachia in previous studies and the diversity found in the sequences analysed, suggests horizontal transmission to these sandflies.

Glenohumeral arthrodesis for the treatment of recurrent shoulder instability in epileptic patients.

We report our experience with glenohumeral arthrodesis as a salvage procedure for epilepsy-related recurrent shoulder instability. A total of six patients with epilepsy underwent shoulder fusion for recurrent instability and were followed up for a mean of 39 months (12 to 79). The mean age at the time of surgery was 31 years (22 to 38). Arthrodesis was performed after a mean of four previous stabilisation attempts (0 to 11) in all but one patient in whom the procedure was used as a primary treatment. All patients achieved bony union, with a mean time to fusion of 2.8 months (2 to 7). There were no cases of re-dislocation. One revision was undertaken for loosening of the metalwork, and then healed satisfactorily. An increase was noted in the mean subjective shoulder value, which improved from 37 (5 to 50) pre-operatively to 42 (20 to 70) post-operatively although it decreased in two patients. The mean Oxford shoulder instability score improved from 13 pre-operatively (7 to 21) to 24 post-operatively (13 to 36). In our series, glenohumeral arthrodesis eliminated recurrent instability and improved functional outcome. Fusion surgery should therefore be considered in this patient population. However, since the majority of patients are young and active, they should be comprehensively counselled pre-operatively given the functional deficit that results from the procedure.

Operative versus non-operative treatment for two-part surgical neck fractures of the proximal humerus.

INTRODUCTION: Aim of this study was to evaluate outcomes of operative as compared to conserveative treatment for two-part humerus fractures at the surgical neck. METHODS: Data from a prospective multi-centre cohort study on four treatment options (conservative treatment and three implants, i.e. LPHP, PHILOS and PHN) for proximal humerus fractures were evaluated in this post hoc analysis. All patients with two-part fractures of the surgical neck (AO types A2, n = 54 and A3, n = 110) were identified and included for the analysis. All operatively treated patients were gathered and compared to those receiving conservative treatment. Primary outcome parameters were pain, range of motion and absolute and relative Constant scores at 3, 6 and 12 months following injury and coronal plane alignment at 12 months. RESULTS: Operative (n = 133) and non-operative (n = 31) groups were comparable with regard to all parameters assessed including mean age (62.9 vs. 65.6, P = 0.479), gender (27 vs. 29 % male, P = 0.826) and fracture distribution (65 vs. 77 % A3 type, P = 0.207). 26 of the 31 conservatively treated and 103 of the 133 operatively treated patients (84 and 77 %, respectively) were available for final follow-up. There was a continuous improvement for all outcome parameters in both treatment groups (P < 0.001). Operative treatment resulted in a more effective reduction of pain at 3 months (51 vs. 76 % reporting pain at fracture site, P = 0.03) and a reduction of coronal plane malalignment. Both range of motion and Constant scores were, however, comparable in both groups at all follow-up visits. Relative and absolute Constant scores were generally excellent at final follow-up (74 vs. 74, P = 0.528 and 89 vs. 91, P = 0.494, respectively). CONCLUSIONS: Both non-operative treatment and operative treatment using modern implants (LPHP, PHILOS and PHN) can be considered safe and effective treatment options for two-part fractures of the proximal humerus. Operative treatment may result in better range of motion and reduced pain in the early postoperative course of treatment.

Instability of the sternoclavicular joint: current concepts in classification, treatment and outcomes.

The sternoclavicular joint (SCJ) is a pivotal articulation in the linked system of the upper limb girdle, providing load-bearing in compression while resisting displacement in tension or distraction at the manubrium sterni. The SCJ and acromioclavicular joint (ACJ) both have a small surface area of contact protected by an intra-articular fibrocartilaginous disc and are supported by strong extrinsic and intrinsic capsular ligaments. The function of load-sharing in the upper limb by bulky periscapular and thoracobrachial muscles is extremely important to the longevity of both joints. Ligamentous and capsular laxity changes with age, exposing both joints to greater strain, which may explain the rising incidence of arthritis in both with age. The incidence of arthritis in the SCJ is less than that in the ACJ, suggesting that the extrinsic ligaments of the SCJ provide greater stability than the coracoclavicular ligaments of the ACJ. Instability of the SCJ is rare and can be difficult to distinguish from medial clavicular physeal or metaphyseal fracture-separation: cross-sectional imaging is often required. The distinction is important because the treatment options and outcomes of treatment are dissimilar, whereas the treatment and outcomes of ACJ separation and fracture of the lateral clavicle can be similar. Proper recognition and treatment of traumatic instability is vital as these injuries may be life-threatening. Instability of the SCJ does not always require surgical intervention. An accurate diagnosis is required before surgery can be considered, and we recommend the use of the Stanmore instability triangle. Most poor outcomes result from a failure to recognise the underlying pathology. There is a natural reluctance for orthopaedic surgeons to operate in this area owing to unfamiliarity with, and the close proximity of, the related vascular structures, but the interposed sternohyoid and sternothyroid muscles are rarely injured and provide a clear boundary to the medial retroclavicular space, as well as an anatomical barrier to unsafe intervention. This review presents current concepts of instability of the SCJ, describes the relevant surgical anatomy, provides a framework for diagnosis and management, including physiotherapy, and discusses the technical challenges of operative intervention.

Management of peri-prosthetic fracture of the humerus with severe bone loss and loosening of the humeral component after total shoulder replacement.

There is little information about the management of peri-prosthetic fracture of the humerus after total shoulder replacement (TSR). This is a retrospective review of 22 patients who underwent a revision of their original shoulder replacement for peri-prosthetic fracture of the humerus with bone loss and/or loose components. There were 20 women and two men with a mean age of 75 years (61 to 90) and a mean follow-up 42 months (12 to 91): 16 of these had undergone a previous revision TSR. Of the 22 patients, 12 were treated with a long-stemmed humeral component that bypassed the fracture. All their fractures united after a mean of 27 weeks (13 to 94). Eight patients underwent resection of the proximal humerus with endoprosthetic replacement to the level of the fracture. Two patients were managed with a clam-shell prosthesis that retained the original components. The mean Oxford shoulder score (OSS) of the original TSRs before peri-prosthetic fracture was 33 (14 to 48). The mean OSS after revision for fracture was 25 (9 to 31). Kaplan-Meier survival using re-intervention for any reason as the endpoint was 91% (95% confidence interval (CI) 68 to 98) and 60% (95% CI 30 to 80) at one and five years, respectively. There were two revisions for dislocation of the humeral head, one open reduction for modular humeral component dissociation, one internal fixation for nonunion, one trimming of a prominent screw and one re-cementation for aseptic loosening complicated by infection, ultimately requiring excision arthroplasty. Two patients sustained nerve palsies. Revision TSR after a peri-prosthetic humeral fracture associated with bone loss and/or loose components is a salvage procedure that can provide a stable platform for elbow and hand function. Good rates of union can be achieved using a stem that bypasses the fracture. There is a high rate of complications and function is not as good as with the original replacement.

The outcome of scapulothoracic fusion for painful winging of the scapula in dystrophic and non-dystrophic conditions.

Scapulothoracic fusion (STF) for painful winging of the scapula in neuromuscular disorders can provide effective pain relief and functional improvement, but there is little information comparing outcomes between patients with dystrophic and non-dystrophic conditions. We performed a retrospective review of 42 STFs in 34 patients with dystrophic and non-dystrophic conditions using a multifilament trans-scapular, subcostal cable technique supported by a dorsal one-third semi-tubular plate. There were 16 males and 18 females with a mean age of 30 years (15 to 75) and a mean follow-up of 5.0 years (2.0 to 10.6). The mean Oxford shoulder score improved from 20 (4 to 39) to 31 (4 to 48). Patients with non-dystrophic conditions had lower overall functional scores but achieved greater improvements following STF. The mean active forward elevation increased from 59° (20° to 90°) to 97° (30° to 150°), and abduction from 51° (10° to 90°) to 83° (30° to 130°) with a greater range of movement achieved in the dystrophic group. Revision fusion for nonunion was undertaken in five patients at a mean time of 17 months (7 to 31) and two required revision for fracture. There were three pneumothoraces, two rib fractures, three pleural effusions and six nonunions. The main risk factors for nonunion were smoking, age and previous shoulder girdle surgery. STF is a salvage procedure that can provide good patient satisfaction in 82% of patients with both dystrophic and non-dystrophic pathologies, but there was a relatively high failure rate (26%) when poor outcomes were analysed. Overall function was better in patients with dystrophic conditions which correlated with better range of movement; however, patients with non-dystrophic conditions achieved greater functional improvement.

Making history: Thomas Francis, Jr, MD, and the 1954 Salk Poliomyelitis Vaccine Field Trial.

This article focuses on the poliomyelitis vaccine field trial directed by Thomas Francis,Jr, MD, of the University of Michigan Vaccine Evaluation Center and sponsored by the National Foundation for Infantile Paralysis (NFIP) or, as it was better known to the public, the March of Dimes. It was a landmark in the widescale testing of a vaccine and the ethical use of human subjects. Millions of American parents readily volunteered their healthy children to participate. A total of 150,000 volunteers, including schoolteachers, physicians, nurses, and health officers all endorsed the study and donated their time and effort to make it successful. Avoiding the use of marginalized groups, the field trial purposefully did not involve institutionalized children; instead, it was based in 15,000 public schools in 44 of the 48 states as clinic sites. A group of 650,000 children received some type of injection, either the vaccine or a placebo, and another 1.18 million served as controls. The field trial depended, most essentially, on both public support and the participation of millions of children who remained enrolled in a study that required a series of 3 injections and a 6-month evaluation period. Enlisting the huge number of participants presented practical examples of the difficulties in experimenting on human subjects. On April 26, 1954, Randy Kerr, a participant or "Polio Pioneer" as the children involved were called, received the first inoculation of the Salk poliomyelitis vaccine. The nationwide study "designed to test the safety and efficacy" of the Salk vaccine had officially begun.

On the timing of soft-tissue reconstruction for open fractures of the lower leg.

The timing of soft-tissue reconstruction for severe open fractures of the lower leg is considered crucial to the later outcome, and yet pertinent publications are few. The purpose of this study was to add some based on evidence arguments for the choice of the most adequate timing in the management of these injuries. Twenty-nine consecutive open fractures of the tibia, including 24 grade 3B and 5 grade 3C fractures, were treated using a protocol of immediate debridement, early definitive skeletal stabilisation and early soft-tissue reconstruction. Fifteen lower legs were reconstructed after a mean delay of 4.4 days (range 1-9 days), while 14 lower legs were reconstructed immediately, i.e. as an emergency procedure on the day of admission. Both groups were comparable for sex, age, type of trauma, associated general injuries, type of fracture, associated arterial lesion, associated tendon rupture, type of soft-tissue reconstruction and duration of follow-up. All patients were reviewed at a mean follow-up of 47 months (range 15-89 months). In the delayed reconstruction group the time to full, unprotected weight-bearing (P = 0.0021), the time to definitive union (P = 0.0049), the number of reoperations (P = 0.0001) and the infection rate (P = 0.0374) were significantly higher. The data suggest that immediate reconstruction is, the general condition of the patient permitting, the timing of choice for soft-tissue coverage.

The deltoid extension lag sign for diagnosis and grading of axillary nerve palsy.

The deltoid extension lag sign has been developed to avoid the pitfalls confounding the diagnosis of an axillary nerve lesion. The physician elevates the arm into a position of near full extension. The patient is asked to attempt active maintenance of this position. If the deltoid is weak, the arm will drop. In five patients with traumatic axillary nerve palsy after anterior dislocation of the shoulder, the deltoid extension lag sign was used to evaluate the functional status of the deltoid muscle. The magnitude of the angular drop, or lag, of the arm was a precise indicator of the functional status and recovery of the deltoid. The sign proved to be objective and reproducible, allowing confident assessment of deltoid function and when repeated over time allowed precise follow-up of deltoid recovery.

Decortication and plate osteosynthesis for nonunion of the clavicle.

Between 1968 and 1995, 37 patients with ununited fractures of the clavicle were treated by decortication and plate osteosynthesis. Thirty-two (86%) were failures of union of fractures of the middle third. Thirty-four (92%) patients had post-traumatic nonunion or delayed union. Sixteen (43%) patients had undergone primary operative treatment. Autogenous cancellous bone graft was used in 24 (65%) patients with atrophic nonunion. Nine tricortical, iliac crest, intercalary grafts were used for segmental bone loss equal to or greater than 15 mm. At the end of treatment, union had been achieved in 35 (95%) cases. At a mean follow-up of 8.6 years (range 13 months to 17 years), 32 (86%) patients had no symptoms and had a full range of motion of the shoulder. Decortication with plate osteosynthesis is a reliable, durable technique for the management of symptomatic, ununited fractures of the clavicle.

Allograft reconstruction of segmental defects of the humeral head for the treatment of chronic locked posterior dislocation of the shoulder.

The recognized options for the treatment of chronic locked posterior dislocation of the shoulder are dependent on the size of the anteromedial defect of the humeral head. Transfer of the lesser tuberosity with its attached subscapularis tendon into the defect is recommended for defects that are smaller than approximately 40 per cent of the joint surface. Prosthetic replacement is preferred for larger defects. Four consecutive patients who had a chronic locked posterior dislocation of the glenohumeral joint associated with a defect of the humeral head that was at least 40 per cent of the articular surface were managed with reconstruction of the shape of the humeral head with use of an allogeneic segment of the femoral head. Stability was restored and maintained in each patient at an average of sixty-eight months (range, sixty to seventy-six months) after the procedure. Three patients reported little or no pain and no or slight functional restrictions in the activities of daily living, and they considered the result to be satisfactory. The fourth patient had mild pain and moderate-to-severe dysfunction secondary to avascular necrosis of the remaining portion of the humeral head after a symptom-free period of six years.

Fractures of the humeral capitellum: Herbert screw fixation.

During the first half of 1991, five patients with displaced fractures of the humeral capitellum were managed by open reduction and fixation of the capitellar fragments with Herbert bone screws. All patients had stable, painfree elbows at follow-up, with no restriction of normal daily activities. There were no evidence of early avascular necrosis of capitellar fragments, even where soft tissue attachments of small fragments had been injured. This method of fixation allows accurate restoration of the articular surface of the humero-radial joint and may therefore contribute to the excellent functional results following this injury in these patients.

Transfer of multiply-injured patients for neurosurgical opinion: a study of the adequacy of assessment and resuscitation.

A total of 21 consecutive referrals with multiple injuries (Injury Severity Score (ISS) 17-66), admitted into the Regional Neurosurgical Unit (RNSU) over a 1-year period from August 1989, was analysed to evaluate the risks associated with transfer of such patients from district general hospitals within the North West Thames Region. Injury assessment was deficient in nine cases. Four developed hypovolaemic shock during transfer, and in five resuscitation was inadequate. Four had minor head injuries and two had no head injury; of these cases, one died. There were four fatalities: the mean ISS in this group was 42, and in all cases deficiencies in resuscitation and assessment before transfer were identified. There were seven major missed injuries. All patients had musculoskeletal injuries and 16 required orthopaedic intervention within 6 h. Interhospital transfer of this group of patients carries significant risks, may be unnecessary, and may delay other surgical priorities.

Modification of guanine nucleotide-regulatory components in brain membranes. I. Changes in guanosine 5'-triphosphate regulation of opiate receptor-binding sites.

Guanine nucleotides regulate binding of opiate agonists to membrane receptors by increasing agonist dissociation rates. The current study demonstrates that the ability of guanosine 5'-triphosphate (GTP) and its nonhydrolyzable analogue guanylyl-5'-imidodiphosphate (Gpp(NH)p) to inhibit opiate agonist binding to rat brain membranes can be altered by two methods: by preincubating with EDTA, and by preincubating at pH 4.5. EDTA pretreatment increased the potency of Gpp(NH)p in inhibiting [3H]morphine binding by 4-fold, with little apparent change in the maximum effect of Gpp(NH)p or on levels of binding itself. The effect of EDTA pretreatment was blocked by prior incubation of membranes with excess calcium or manganese but could not be reversed by any divalent cation if the EDTA incubation was longer than 10 min. EDTA pretreatment increased the effects of GTP on dissociation rates of agonists. Pretreatment of membranes at pH 4.5 increased the ability of guanine nucleotides to regulate agonist binding by increasing the maximum effect of Gpp(NH)p from 50% to 80% inhibition of [3H]morphine binding with minor increase in potency of Gpp(NH)p. The actions of EDTA and low pH pretreatments were additive when both were conducted on the same membranes. These results suggest that modification of brain membranes can alter the interaction of receptors with guanine nucleotide-regulatory components which may lead to changes in post-receptor membrane events.

Selective alterations in guanine nucleotide regulation of opiate receptor binding and coupling with adenylate cyclase.

Pretreatment of rat brain membranes at pH 4.5 increased GTP and Gpp(NH)p regulation of [3H]-D-ala2-met5-enkephalinamide (D-ala-enk) binding with no change in absolute binding itself. Pretreatment at pH 4.5 did not alter basal adenylate cyclase activity but did cause a loss (50-90%) in NaF- and Gpp(NH)p-stimulated activity, indicating a functional loss of GTP-coupling proteins. The addition of cis-vaccenic acid partially restored NaF- and Gpp(NH)p-stimulated cyclase after low pH pretreatment but, in the same membranes, did not reverse the increase in GTP regulation of agonist binding. These results suggest that GTP regulation of binding and stimulation of adenylate cyclase occur by fundamentally different mechanisms.