Comparison of total and partial traumatic tears of the subscapularis tendon.

We treated surgically 16 shoulders with an isolated traumatic rupture of the subscapularis tendon over a six-year period. Nine patients had a total and seven a partial tear of the subscapularis tendon. Repair was undertaken through a small deltopectoral groove approach. The mean Constant score improved in total tears from 38.7 to 89.3 points (p = 0.003) and in partial tears from 50.7 to 87.9 points (p = 0.008). The total tears were significantly more improved by surgery than the partial tears (p = 0.001). The delay between trauma and surgery was inversely proportional to the improvement in the Constant score suggesting that early diagnosis and surgical repair improves outcome.

[Limitation of shoulder mobility due to ankylosis of the sternoclavicular joint in SAPHO syndrome]. / Das SAPHO-Syndrom als Ursache von Bewegungseinschränkungen der Schulter.

The rare case of limited range of motion of the shoulder due to ankylosis of the sternoclavicular joint in SAPHO syndrome is presented. The symptoms and the resection arthroplasty of the sternoclavicular joint are discussed.

[Treatment of trochanteric fractures with the gamma nail]. / Die Versorgung trochanterer Frakturen mit dem Gammanagel.

The osteosynthesis of trochanteric fractures requires a minimal invasive technique to guarantee fully weight bearing and early rehabilitation in elderly patients. In this retrospective study we want to prove if the gamma nail meets all requirements and if the results improved after initiation of the new instrumentarium and standardization of the operative technique. From January 1992 until April 2000 we treated 387 patients with a gamma nail. The average age was 79.4 years. We used the new instrumentarium suitable for radiography since June 1996, the operative technique was standardized since the same time. The evaluation occurred on the basis of clinical and radiological findings included analysis of complications. We've seen intraoperative problems in 29% before June 1996, this rate could be reduced to 9%. General postoperative complications presented in equal frequency. After improvement of the technique dislocations of the neck screw and relevant sinking of the fractures were more rarely. The rate of reoperations after complications of the implant was 8% in both groups. In consideration of technical standards the postoperative full weight bearing and early mobilisation is possible even in old patients.

A gene cluster encoding plantaricin 1.25beta and other bacteriocin-like peptides in Lactobacillus plantarum TMW1.25.

Plantaricin 1.25beta is a thermostable class two bacteriocin produced by Lactobacillus plantarum TMW1.25 isolated from sausage fermentation. It is co-produced with several other bacteriocin-like peptides. Using oligonucleotides derived from previously determined peptide sequences, a 3.8 kb DNA fragment could be amplified. A neighboring 1.8 kb fragment was amplified using ligation-anchored single-specific-primer PCR. Sequencing of the complete 5.6 kb stretch revealed that the structural gene for plantaricin 1.25beta, plnB, was located downstream of another bacteriocin gene, plnC. Seven other open reading frames were detected, including plnK encoding a bacteriocin-like peptide, but not including any putative immunity genes. Interestingly, the gene cluster contained an IS30-like insertion sequence, designated IS125, as well as an ISS1 homolog.

Purification and partial amino acid sequence of plantaricin 1.25 alpha and 1.25 beta, two bacteriocins produced by Lactobacillus plantarum TMW1.25.

Two bacteriocins produced by Lactobacillus plantarum TMW1.25 have been purified by a four-step purification procedure, including ammonium sulphate precipitation and cation-exchange chromatography followed by hydrophobic-interaction chromatography on octyl sepharose. The final purification was performed by repeated reversed-phase chromatography steps which yielded two bacteriocin fractions designated plantaricin 1.25 alpha and plantaricin 1.25 beta. The molecular masses of the peptides in these fractions were 5979 and 5203 Da, respectively. Combination of the fractions did not have any synergistic effects on bacteriocin activity, indicating that they each contain a one-peptide bacteriocin. The major peptide in the alpha fraction was blocked at its N-terminus, and a partial sequence (25 residues) could only be obtained after cleavage with CNBr. This sequence did not show clear homologies with known bacteriocins. The beta peptide has been sequenced almost completely and consists, presumably, of 53 residues. This peptide displayed strong homology to the known N-terminal part of brevicin 27 produced by Lactobacillus brevis SB27. The results showed that the beta peptide contains as many as six consecutive lysine residues at the N-terminus.

[Antegrade or retrograde intramedullary nailing in diaphyseal or sub-capital humeral fractures in the adult]. / Enclouage ou embrochage centromedullaire lors de fractures humerales diaphysaires et sous-capitales chez l'adulte.

The aim of this retrospective study was the evaluation of three current medullary nailing techniques and their approach related problems in diaphyseal and proximal humeral fractures. 28 patients (15 female, mean age 65 y; 13 male, mean age 53 y) with either diaphyseal (n = 22) or proximal humeral (n = 6) fractures treated with different nailing systems were reviewed (mean follow up 18.3 months). Two main groups were formed according to the surgical approach: an anterograde nailing group (AN), stabilized with Seidel (Howmedica) nails (n = 12) versus a retrograde nailing group (RN) with either Prévot (Landos) nails (n = 7) or Hackethal (Ulrich) nails (n = 9). The two groups were comparable regarding to age, follow up and fracture type. The subjective scores (global function, all day activity, pain, ROM) of the two groups (AN and RN) showed no statistically significant differences. Subacromial impingement led to reoperation in 50% (6/12) of the AN patients (Seidel nail). In 3/16 patients a reoperation was necessary due to secondary proximal or distal nail migration (Hackethal or Prévot nails). Delayed union was found either in one. Seidel or one Prévot nailed humerus. No postoperative infections or neurological problems (3 preoperative radial palsies recovered) due to the operative pro cedure were seen. The AN related subacromial impingement seems to be more disabling than RN related reduction of elbow function (extension deficit).

Segmental avascularity of the humeral diaphysis after reamed intramedullary nailing.

Although the clinical experience with reamed intramedullary nailing has been successful for the treatment of femur and tibia fractures, similar success has not been duplicated when this technique has been applied in the humerus. Although the cortical vascular response to nailing of the humerus is presently assumed to be similar to that of the femur, the response of the humerus to reaming has not been documented in vivo. The following case depicts avascularity of the humeral diaphyseal cortex as a complication of reamed intramedullary nailing and illustrates the sensitivity of the humerus to this treatment.

Strength recovery in fractured sheep tibia treated with a plate or an internal fixator: an experimental study with a two-year follow-up.

OBJECTIVES: Comparison of fracture healing with two different implants: a conventional Dynamic Compression Plate (DCP) and a new internal Point Contact Fixator (PC-Fix). DESIGN: Randomized, prospective study in experimental animals. Observation times: 12, 24, 48 and 96 weeks, with six sheep per group. SETTING: Following surgery, animals were kept with unrestricted weight-bearing in individual stalls for 12 weeks, thereafter in groups. ANIMALS: 56 adult Swiss mountain sheep. INTERVENTION: A standardized oblique fracture of the sheep tibia was reduced and compressed by a lag screw and "neutralized" with one of the implants. MAIN OUTCOME MEASUREMENTS: Standard radiographs were used for callus size measurements. After sacrifice the implant was removed and both the treated bone and the contralateral bone were tested for static strength in bending with the plate side under tension. Broken bones were processed for histological evaluation. RESULTS: In the DCP group all six bones failed through the original fracture at 12 weeks. At 24 and 48 weeks two out of six, at 96 weeks one out of six bones failed through the original fracture, others through one of the screw holes. In the PC-Fix group there were no failures through the original fracture with a single exception at 96 weeks. The strength values in the PC-Fix groups of 12 and 96 weeks were significantly higher then in the corresponding DCP groups. CONCLUSIONS: Healing of simple diaphysial fractures treated by PC-Fix was superior to that achieved by conventional plating. The histological evaluation suggested that the observed differences can be accounted for by the absence of implant-related cortical necrosis and by the circumferentially uninterrupted (if smaller) callus in the PC-Fix group.

A simple technique for creating hybrid fixators using a modified AO single adjustable clamp.

Hybrid external fixators with limited internal fixation have become popular in the treatment of complex intraarticular fractures of the tibia. A wide variety of hybrid external fixation systems are commercially available, but these frames are expensive and not always readily available. The authors present a simple hybrid frame constructed from the AO tubular and Ilizarov type external fixator sets using a modified AO single adjustable clamp. This hybrid frame is easy to apply, versatile, and significantly less expensive than other commercially available adaptors and frames.

The torsional strength of bones with residual screw holes from plates with unicortical and bicortical purchase.

OBJECTIVE: To evaluate the effect of unicortical and bicortical screw holes on residual bone strength by comparing the in vitro torsional strength of cadaveric sheep tibiae with screw holes from plates with unicortical and bicortical purchase relative to each other and to intact bone. DESIGN: The paired tibiae were grouped randomly and torsion tested to failure as follows: Group I -- unicortical screw holes versus intact bone; Group II -- bicortical screw holes versus intact bone; and Group III -- bicortical versus unicortical screw holes. BACKGROUND: Recently the point contact fixator, or PC-Fix (using screws with unicortical purchase), was designed to minimize bone devascularization beneath the plate compared to the conventional dynamic compression plate, or DCP (bicortical purchase), and possibly reduce refracture rates after plate removal. However, the effects of unicortical versus bicortical residual screw holes on potential refracture are unknown. METHODS: Screw holes were drilled and tapped through either a 7-hole bicortical DCP or a unicortical PC-Fix in 18 paired cadaveric sheep tibiae. The bones were then tested in torsion. RESULTS: The average decreases in the torsional strength of unicortical screw holes versus intact bone, bicortical screw holes versus intact bone, and bicortical versus unicortical screw holes were 21.6, 31.4, and 26.7% respectively. Mean torque values to failure were statistically significant within each of the three groups: P<0.01, 0.001, and 0.001 respectively. CONCLUSIONS: Bones with unicortical screw holes are significantly weaker in torsion than intact bones, but significantly stronger than bones with bicortical holes. RELEVANCE: Refracture after hardware removal is a recognized clinical complication of the traditional bicortical screw fixation. In combination with the demonstrated biological advantages, implants with unicortical purchase may be associated with less risk for early refracture upon removal.

[Treatment of unstable distal radius fractures with a small AO-fixateur externe not bridging the joint]. / Die Behandlung instabiler distaler Radiusfrakturen mit dem nicht gelenküberbrückenden kleinen AO-Fixateur externe.

This retrospective study investigated the stability of the small AO external fixator in a radioradial configuration used in the treatment of 42 mostly unstable distal radius fractures (types A-3.2, C-1.2 and C-2.1 according to the AO classification). No bone grafting was performed. All cases were documented with antero-posterior and lateral X-rays preoperatively, 0, 2 and 6 weeks postoperatively and after consolidation. Early functional aftertreatment was started one week after surgery. Thirty-six fractures showed a dorsal comminution, combined with osteopenia in 18 cases. The mean preoperative radial angle of 17 degrees was normalized to 25 degrees postoperatively. The mean preoperative volar angle of minus 30 degrees was reduced to 12 degrees postoperatively. None of these mean angles changed until consolidation. The external fixator was removed on average after 7 weeks (range 6-10 weeks) depending on the radiological fracture healing. The small AO external fixator in a radioradial configuration proved to be stable enough for early functional aftertreatment of the wrist. Its stability is related to a proper operative technique and correct indication (unstable Colles type with one or two distal fragments). Bone grafting is unnecessary if the external fixator is left in situ until bony consolidation.

[Percutaneous iliosacral screw fixation of vertical unstable pelvic ring fractures]. / Die perkutane iliosakrale Verschraubung von vertikal instabilen Beckenringfrakturen.

In type C pelvic ring fractures ORIF is the treatment of choice. Early definitive fixation often is not possible due to severe soft tissue injuries and hemorrhage. The percutaneous iliosacral screw fixation with the patient supine offers a minimally invasive and definitive fixation method of the posterior unstable pelvic ring also in acute situations. Our first experience shows that a ventral stabilisation is necessary in combination with one dorsal screw. Both fixations are managed in the supine position of the patient during one anesthesia.

A mechanical comparison of the dynamic compression plate, limited contact-dynamic compression plate, and point contact fixator.

Cortical bone porosis associated with the dynamic compression plate (DCP) prompted the development of the limited-contact dynamic compression plate (LC-DCP) and the point-contact fixator (PC-Fix) to increase bone vascularity. However, the comparative fixation characteristics of the three designs are unknown. Transverse fractures were physiologically created in paired cadaveric sheep tibiae, which were plated before torsion testing and four-point bending to failure. The tibiae were grouped randomly and compared as follows: DCP versus LC-DCP, DCP versus PC-Fix, and LC-DCP versus PC-Fix. Mean torque to failure demonstrated no significant difference between the three plates (p < 0.33). Mean bending stiffness, gap opening, and moment to failure also demonstrated no significant difference between the three designs with p < 0.29, < 0.13, and < 0.16, respectively. The LC-DCP and PC-Fix have torsion and bending properties comparable with the DCP in the fixation of simple transverse diaphyseal fractures.

The pinless external fixator--relevance of experimental results in clinical applications.

The pinless external fixator was intended as a stable, temporary, minimally invasive fixator for severe tibial fractures ensuring safer conversion to an intramedullary nail. An in vitro study showed that the pinless fixator was mechanically not as stiff as the conventional AO tubular device, the main problem being low axial stiffness. This study involving initial clinical trials with the pinless fixator on tibial fractures in St. Gall is based on the experimental work and previous clinical experience of the main author. From June 1992 to June 1994 10 tibial fractures (eight II degrees and III degrees open, one closed with compartment syndrome, one infected non-union) were temporarily stabilized with a pinless fixator. In another patient a calcaneal traction device was applied. The pinless fixator was applied immediately in eight cases and three times as a secondary measure. All patients were scheduled for a secondary change of treatment. The tibiae were stabilized with four clamps and one anterior rod. The clamps were inserted via transverse stab incisions. Intraoperatively the pinless fixator was easy to handle and complications did not occur. Seven different surgeons needed an average of 20 minutes for insertion. Postoperative care was the same as for conventional fixators. Six patients were treated secondarily with an i.m. nail, three with an external fixator on average after 12 days. One patient died on day 1. The pinless fixator failed twice in one patient (incorrect insertion, fall). Reversible pain in the tendons of the foot extensor muscles was noticed. One superficial clamp track infection was seen. All clamps were reused more than three times. The pinless fixator is stable enough for temporary fracture fixation of the tibia in a four clamp one bar construction. A prerequisite for stability is the proper application technique ("grab test", rocking movements). Weight-bearing should be limited to a minimum and needs a compliant patient. The application technique is easy to learn suggesting that the pinless fixator could be an ideal tool for emergency stabilization. The primary application of this fixator leaves all further treatment modalities open (repeated debridements, evaluation of the open fracture). It may also be of particular value to many clinicians working with reamed nails as their only secondary treatment option for open tibial fractures.

Mechanical properties of the Pinless external fixator on human tibiae.

UNLABELLED: In the treatment of either acute severe open tibial fractures or their sequelae, a convenient external fixator is desirable. The conventional transosseous fixation with pins entering the medullary cavity is associated with problems such as pin loosening and pin track infection. Due to the bacterial contamination of the medullary space via the pin track the change of treatment from primary external fixation to secondary medullary nailing is an infection risk. In order to minimize these problems an external clamp fixator, the Pinless, was created. Medullary penetration is avoided by substitution of the conventional pins with clamps. The latter are inserted by hand (removable handles) and anchored only in the bone cortex. The medullary cavity stays intact. But is this clamp fixation stable enough for clinical use? MATERIAL AND METHODS: On paired human cadaver tibiae, we compared the mechanical properties of the experimental Pinless, the conventional AO-tubular fixator and the Ultra-X fixator. Clamps differing in size (small/large) and material (steel/titanium) were used and compared to Schanz screws (steel, 5.0 mm diameter). We measured the stiffness of comparable configurations (1 or 2 bars) under axial compression, four-point-bending in two planes, and torsion. The pull-out force of the different clamps in relation to the bone diameter and number of rocking movements during insertion was also determined. RESULTS: The Pinless configurations with small clamps and 1 bar showed stiffness values as follows (as a percentage of the corresponding AO-tubular fixator): 42/36% (steel/titanium clamp) axial stiffness, 61/43% bending stiffness perpendicular to the reference plane, 78/79% bending stiffness parallel to the reference plane, and 90/95% torsional stiffness. The corresponding Ultra-X device was not as stiff as the Pinless. The use of two longitudinal rods increased the relative stiffness only under axial compression. The mean pull-out force on the proximal tibia was 1011 N for the small steel clamp, 717 N for the large steel clamp, 681 N for the small and 777 N for the large titanium clamp. At the lowest tibial diameter the values were reduced by 10 to 43%. The rocking movements doubled the pull-out force, e.g. there was a pull-out force for the large clamp of 600 N with five rocking movements compared to 310 N without. DISCUSSION: The Pinless was not as stiff as the conventional AO-tubular device but stiffer than the clinically used Ultra-X, especially in sagittal bending, the main load on a tibial fracture in the first weeks after trauma.(ABSTRACT TRUNCATED AT 400 WORDS)