Novel endoscopic sacroiliac screw removal technique: reduction of intraoperative radiation exposure.

OBJECTIVE: We report in the following on our technique of endoscopic sacroiliacal screw removal as a new extra-articular endoscopic method in soft tissue surgery, aimed at the reduction of radiation exposure for both the patient and the surgical teams. Patients who underwent endoscopic implant removal from the dorsal pelvic ring (Group A) were retrospectively compared with a control group, in which the screws were removed via the conventional approach (Group B). The parameters of interest were the extent of x-ray exposure in seconds and surgical duration in minutes as well as approach related peri- and postoperative complications. RESULTS: 34 screws were removed endoscopically from 28 patients in group A and 35 screws from 29 patients in group B. The mean skin-to-skin time in group A was 36.1 (15-111) min and 32.7 (12-114) min in group B. The difference was not statistically significant (p > 0.05). The average radiation time in group A was 5.7 ± 3.2 s (range, 0-101 s), while in group B the radiation time was significantly longer (52.6 ± 23 s (range, 0-239 s); p = 0.005). CONCLUSIONS: Endoscopic screw removal from the posterior pelvic ring reduces the intraoperative radiation time whereas the skin-to-skin times do not differ from the conventional procedure. LEVEL OF EVIDENCE: Case-control study, Level III.

Similar outcomes for nail versus plate fixation of three-part proximal humeral fractures.

BACKGROUND: There is a lack of consensus regarding optimal surgical management of displaced and unstable three-part proximal humeral fractures. QUESTIONS/PURPOSES: The objective of this prospective observational study was to compare the clinical and radiologic outcomes of plate versus nail fixation of three-part proximal humeral fractures. PATIENTS AND METHODS: Two hundred eleven patients with unstable three-part proximal humeral fractures were treated with ORIF using plate (PHILOS [proximal humeral interlocking system]/LPHP [locking proximal humerus plate]) or nail (PHN [proximal humeral nail]) osteosynthesis. Outcome measurements included pain, Constant and Murley and Neer scores, and the occurrence of complications at 3, 6, and 12 months postsurgery. Regression analysis and the likelihood ratio test were used to evaluate differences between the cohorts. RESULTS: Throughout the 1-year followup period the Constant and Murley scores improved significantly for both cohorts; there was no significant difference between the nail group compared with the plate group. Also, 1-year Neer scores were similar between the two cohorts. Patients in the PHN group perceived significantly less pain compared with patients in the plate fixation group at 3, 6 and 12 months after surgery. We observed 79 local complications in 60 patients with no significant risk difference between the treatment groups; 35 intraoperative complications were directly related to the initial surgical procedure. CONCLUSIONS: The similar 1-year outcomes for nail versus plate fixation of three-part proximal humeral fractures suggest that both techniques may be useful for internal fixation of these fractures. Many complications were related to incorrect surgical technique and therefore can be avoided. Advanced surgical skills and experience are considered to be more critical for successful operative treatment of three-part proximal humeral fractures than the selection of the implant. LEVEL OF EVIDENCE: Level II, therapeutic study (prospective comparative study). See the Guidelines for Authors for a complete description of levels of evidence.

Comparison of two different locking plates for two-, three- and four-part proximal humeral fractures--results of an international multicentre study.

PURPOSE: The aim of this study was to compare the functional outcome, quality of restoration, and complication rate after open reduction and internal fixation (ORIF) of displaced or unstable 2-, 3- and 4-part humeral fractures using two different locking plates. METHODS: The data used in this analysis was prospectively collected in two large multicentre studies in 15 European Level 1 trauma centres. A total of 318 patients with proximal humeral fractures were treated with ORIF using either the locking proximal humerus plate (LPHP) or proximal humeral internal locking system (PHILOS). Outcome measurements included Constant and Neer scores, evaluation of local pain at the fracture site and complications, and radiographic assessment at one year. RESULTS: At one year, the mean Constant scores (relative to the contralateral shoulder) improved significantly for both groups and were above 80% for 2-, 3-, and 4-part fractures. A significantly shorter surgical time, less pain at the fracture site, and better functional outcome was achieved by PHILOS-treated patients with 2-part fractures throughout the one-year follow-up month and with 3-part fractures at three months (p < 0.05). There was no difference between the treatment outcomes for 4-part fractures, and no difference in the complication rates (p > 0.05). CONCLUSIONS: PHILOS and LPHP can be considered as useful implants for ORIF of displaced and unstable proximal humeral fractures. There was a slight advantage of the PHILOS system with regard to operative time and functional outcome, especially for the treatment of 2- and 3-part fractures.

Path analysis of factors for functional outcome at one year in 463 proximal humeral fractures.

BACKGROUND: Path analysis methods were used to test the prognostic value of 10 patient-related and treatment-related factors on the 1-year functional outcome of 463 proximal humeral fractures measured using the Constant score. Complex inter-relationships between these factors were also evaluated. MATERIALS AND METHODS: Data were collected from a prospective cohort study that included 3 operative groups repaired using nail or plate fixation and 1 nonoperative group. From the available information, various factors potentially having a direct influence on the functional Constant score were identified. The process of creating a hypothetical causal path diagram was undertaken to order the factors in a sequence of associations or cause-and-effect relationships. RESULTS: Our final multivariable regression model for the 1-year Constant score included the 6 factors of age, sex, treatment, occurrence of intraoperative and local post-treatment complications, and anatomic restoration. Being a woman aged older than 40 years, treated with a locking proximal humeral plate (LPHP), having experienced intraoperative and local post-treatment complications, and varus deformity of more than 30° were negative predictors of the Constant score (ie, poor shoulder function 1 year after treatment initiation). Three factors, the dominant side fractured and the Neer and AO fracture type, showed only significant association on intermediate factors. The presence of concomitant disease did not show any significant direct or indirect effect. A final pathway outlines these associations and inter-relationships. CONCLUSION: Prevention of local complications, in particular those leading to severe varus deviation, appears essential to improve shoulder function after a proximal humeral fracture.

Partial weightbearing is not necessary after cementless total hip arthroplasty: a two-year prospective randomized study on 100 patients.

The purpose of this study was to evaluate the effects of partial and full weightbearing after cementless total hip arthroplasty over a two year follow-up period. Fifty-nine women and 41 men (average age 61 years) received an uncemented Spotorno stem and were randomised into a full and a partial weightbearing group. No significant difference was found between the groups with regard to the Merle d' Aubigne hip score, VAS pain level, shaft migration or radiographic signs of bony ingrowth. All femoral components seemed radiologically well-fixed and showed bone ingrowth at 24 months. Provided that solid initial fixation is obtained full weightbearing immediately after cementless total hip arthroplasty using a hydroxyapatite-coated Spotorno-type femoral shaft component can be recommended.

Computer navigation in balloon kyphoplasty reduces the intraoperative radiation exposure.

STUDY DESIGN: Comparison of the dose area product (DAP), the radiation time and the operation time during computer navigated and conventional balloon kyphoplasty procedures. OBJECTIVE: To compare the patients radiation exposure and operation time in a balloon kyphoplasty procedure with and without using a navigation system for the placement of working needles. SUMMARY OF BACKGROUND DATA: Minimal invasive spine surgery is associated with high radiation exposure for both the patient and the surgeon. The use of computer navigation has led to a reduced radiation exposure in experimental trials. To our knowledge, there is no clinical data determining the influence of computer navigation on radiation exposure and operation time in a balloon kyphoplasty procedure. METHODS: Twenty-nine patients with 30 osteoporotic vertebra fractures were treated with a computer-navigated kyphoplasty. The placement of the working needles in thoracic spine fractures was performed after acquiring an intraoperative three-dimensional data set. Fractures of the lumbar spine were treated using fluoroscopic three-dimensional navigation. During each procedure the operation time, the overall radiation time, and the DAP were documented. The data of the navigated operations were compared to a control group of consisting of 30 conventional balloon kyphoplasty procedures. RESULTS: In the conventional kyphoplasty group the average operation times for thoracic spine (ts) and lumbar spine (ls) were 61 and 57 minutes, respectively. The average radiation times were 175 and 165 seconds. The DAP applied to the patient was 1972 and 2105 cGy cm. The average operation times in the navigated group were 67 minutes in the ts and 62 minutes in the ls. The average radiation time was reduced significantly in the navigated group (99 seconds ts and 74 seconds ls). The DAP applied to the patient was also significantly lower (1245 cGy cm (ts) and 1318 cGy cm (ls)). CONCLUSION: The use of computer navigation systems in balloon kyphoplasty procedures reduces the radiation exposure of patients and surgeons significantly. The increased technical effort did not lead to a significant longer operation time. Hence, the use of computer navigation systems in balloon kyphoplasty procedures is recommended.

Fat marrow embolism during intramedullary bone endoscopy: an experimental study in sheep.

We present a study designed to investigate whether the intramedullary bone endoscopy (IBE) procedure within the cavity of an intact long bone will create embolic loads on the lungs similar to that of other orthopedic procedures (e.g., stem implantation in total hip arthroplasty [THA]). In a sheep model, 10 animals underwent the IBE procedure with complete perioperative anesthesiology monitoring. The lungs were harvested postoperatively and examined for fat embolisms. One animal showed evidence of intraoperative fat embolism with temporary increases in mean pulmonary arterial pressure (MPAD) and the mean CO(2)-gradient. The histological examination in this animal revealed fat embolism with a 2% surface area of the investigated fields covered with fat vacuoles. All peri- and postoperative data on the other nine animals were normal. Our findings indicate that, as with other intramedullary manipulation in intact long bones, there is a potential risk for systemic fat excavation during IBE. However, the embolic load is much lower than the rates reported for other orthopedic interventions.

Computer-navigated iliosacral screw insertion reduces malposition rate and radiation exposure.

UNLABELLED: Insertion of percutaneous iliosacral screws with fluoroscopic guidance is associated with a relatively high screw malposition rate and long radiation exposure. We asked whether radiation exposure was reduced and screw position improved in patients having percutaneous iliosacral screw insertion using computer-assisted navigation compared with patients having conventional fluoroscopic screw placement. We inserted 26 screws in 24 patients using the navigation system and 35 screws in 32 patients using the conventional fluoroscopic technique. Two subgroups were analyzed, one in which only one iliosacral screw was placed and another with additional use of an external fixator. We determined screw positions by computed tomography and compared operation time, radiation exposure, and screw position. We observed no difference in operative times. Radiation exposure was reduced for the patients and operating room personnel with computer assistance. The postoperative computed tomography scan showed better screw position and fewer malpositioned screws in the three-dimensional navigated groups. Computer navigation reduced malposition rate and radiation exposure. LEVEL OF EVIDENCE: Level II, therapeutic study.

CT analysis after navigated versus conventional implantation of TKA.

INTRODUCTION: Within a 15-month period, 64 patients underwent 71 primary total knee arthroplasties in a randomized trial comparing the navigated versus the conventional implantation technique. CT scans were chosen for use as imaging procedures pre- and post-operatively to collect data concerning alignment and rotation of the leg as well as the prosthesis. RESULTS: There was no difference between pre- and post-operative data in rotation of the femoral component for navigated versus conventional implantation. The average deviation from the correct long-leg axis was found to be 1.8 +/- 1.3 degrees in the navigated group and 2.5 +/- 1.6 degrees in the conventional group (P < 0.05).

Pectoralis major tendon transfers above or underneath the conjoint tendon in subscapularis-deficient shoulders. An in vitro biomechanical analysis.

BACKGROUND: Different operative techniques for transfer of the pectoralis major tendon have been proposed for the treatment of irreparable ruptures of the subscapularis tendon. The objective of this study was to compare the effects of two techniques of transferring the pectoralis major tendon (above or underneath the conjoint tendon) on glenohumeral kinematics during active abduction in a biomechanical model of a subscapularis-deficient shoulder. METHODS: Six shoulder specimens were tested with a custom dynamic shoulder testing apparatus. After the kinematics of the intact shoulder were recorded, a complete tear of the subscapularis tendon was simulated surgically. A transfer of the clavicular portion of the pectoralis major muscle to the lesser tuberosity was then performed with the transferred tendon placed either above (tendon-transfer 1) or underneath (tendon-transfer 2) the conjoint tendon. For each condition, the maximum abduction angle as well as the external rotation angle and the superoinferior and anteroposterior humeral translations at the maximum abduction angle were recorded. RESULTS: With the rotator cuff intact, the mean maximum glenohumeral abduction angle (and standard error of the mean) was 86.3 degrees +/- 2.1 degrees and the mean amount of external rotation at the maximum abduction angle was 5.5 degrees +/- 7.6 degrees . A complete tear of the subscapularis tendon decreased the mean maximum abduction angle to 40.8 degrees +/- 2.4 degrees (p < 0.001) and increased the mean external rotation to 91.8 degrees +/- 4.8 degrees (p < 0.001). The mean humeral translations in the anterior and superior directions (+3.4 +/- 0.5 and +6.3 +/- 0.3 mm, respectively) at the maximum abduction angle were also increased (p < 0.01 and p < 0.001) when compared with those in the intact shoulder. Significant differences were found in the mean maximum abduction angle as well as the mean external rotation angle and humeral translations (anterior and superior) at maximum abduction between the tendon-transfer-1 condition (63.2 degrees +/- 13.5 degrees , 82.4 degrees +/- 6.6 degrees , 4.0 +/- 1.8 mm, and 3.3 +/- 1.9 mm, respectively) and tendon-transfer-2 condition (89.5 degrees +/- 12.3 degrees , 45.7 degrees +/- 22.5 degrees , -0.6 +/- 2.0 mm, and 0.5 +/- 2.3 mm, respectively). The tendon-transfer-2 condition restored glenohumeral kinematics that were closer to those in the intact shoulder than were those resulting from the tendon-transfer-1 condition. CONCLUSIONS: Transfer of the pectoralis major tendon in subscapularis-deficient shoulders partially restored the glenohumeral kinematics of the intact shoulder. One possible explanation for the superior effect of the tendon-transfer-2 condition is that, with a pectoralis major tendon transfer underneath the conjoint tendon, the line of action of the transferred tendon is closer to that of the subscapularis muscle.

Decreasing glenoid inclination improves function in shoulders with simulated massive rotator cuff tears.

BACKGROUND: A massive rotator cuff tear leads to poor shoulder function as evidenced by diminished glenohumeral abduction and superior translation of the humeral head compared to its normal position. The inclination angle of the glenoid has been associated with rotator cuff tears. The objective of this study was to quantify the effect of a decreased glenoid inclination angle on glenohumeral kinematics during active abduction in shoulders with a simulated, massive rotator cuff tear. METHODS: Eight fresh-frozen full upper extremities were tested using a dynamic shoulder testing apparatus. After recording the kinematics of the intact shoulder, a massive rotator cuff tear was surgically simulated. An osteotomy of the glenoid was then performed and the inclination angle was decreased by 30 degrees . The translation of the humeral head during abduction and the maximum abduction angle were recorded. FINDINGS: With an intact rotator cuff minimal humeral head translation on the glenoid occurred and the maximum abduction angle was mean 85.5 degrees (SD 7.4 degrees ). A massive rotator cuff tear resulted in superior translation of the humeral head with impingement on the acromion. The maximum abduction angle was mean 15.5 degrees (SD 9.4 degrees ). Decreasing the inclination angle of the glenoid resulted in a significant reduction of superior humeral head translation during abduction and there was no impingement on the acromion. The maximum abduction achieved was mean 28.5 degrees (SD 17.0 degrees ). INTERPRETATION: From a clinical perspective the reduced superior translation may decrease shoulder pain since the humeral head no longer impinges on the acromion. Further investigations are necessary to assess if the improvement in abduction is clinically significant.

Thoracohumeral muscle activity alters glenohumeral joint biomechanics during active abduction.

Normal function of the glenohumeral joint depends on coordinated muscle forces that stabilize the joint while moving the shoulder. These forces can either provide compressive forces to press the humeral head into the glenoid or translational forces that may destabilize the glenohumeral joint. The objective of this study was to quantify the effect of pectoralis major and latissimus dorsi muscle activity on glenohumeral kinematics and joint reaction forces during simulated active abduction. Nine fresh-frozen whole upper extremities were tested using a dynamic shoulder testing apparatus. Seven muscle force combinations were examined: a standard combination and 10%, 20%, or 30% of the deltoid force applied to the latissimus dorsi or pectoralis major tendon, respectively. Pectoralis major and latissimus dorsi muscle activity decreased the maximum angle of glenohumeral abduction and external rotation, and increased the maximum horizontal adduction angle compared to the standard muscle combination. Thoracohumeral muscle activity also created a more anteriorly directed joint reaction force that resulted in anterior translation compared to the standard muscle combination. Therefore, the ratio between anteriorly directed translational forces and compressive forces increased during abduction due to this muscle activity, suggesting that thoracohumeral muscle activity may decrease glenohumeral stability based on the joint position and applied loads. A better understanding of the contribution of muscle forces to stability may improve rehabilitation protocols for the shoulder aimed at maximizing compression and minimizing translation at the glenohumeral joint.

Tourniquets may increase postoperative swelling and pain after internal fixation of ankle fractures.

UNLABELLED: Tourniquets frequently are used in orthopaedic surgery to provide a bloodless field. There is still controversy among authors regarding the benefits and potential risks of using a tourniquet. The objective of this prospective randomized study was to quantify the effect of tourniquet use on postoperative swelling, pain, and range of motion after open reduction and internal fixation of ankle fractures. Fifty-four patients with closed ankle fractures were treated surgically; 26 patients were operated on using a thigh tourniquet (Group A), and 28 patients had surgery without the use of a tourniquet (Group B). The groups of patients were similar for age, gender, fracture types, and operative procedures. There was no difference in operation time. Using a tourniquet during open reduction and internal fixation of ankle fractures did increase postoperative swelling and postoperative pain at Day 5 and at Week 6 after surgery. We found a trend for a better range of motion in the ankle until the 6-week followup in the nontourniquet group compared with the group in which the tourniquet was inflated. According to these results we do not recommend using a tourniquet for osteosynthesis of ankle fractures. LEVEL OF EVIDENCE: Therapeutic study, Level I-1 (randomized controlled trial). See the Guidelines for Authors for a complete description of levels of evidence.

Femur-LISS and distal femoral nail for fixation of distal femoral fractures: are there differences in outcome and complications?

We evaluated the functional and radiologic outcomes after stabilization of distal femoral fractures using the distal femoral nail and a less invasive stabilization system to determine if the new implants are superior to other implants (especially the condylar blade plate) regarding the rates of axial deviation, nonunion, and infection and if one of these new implants (Less Invasive Stabilization System, or distal femoral nail) is superior to the other. Two groups, each with 16 patients, were documented prospectively and the results were compared. To record the findings objectively, the Lysholm-Gillquist score was used. A conversion procedure was done in two patients in the plate group and one patient of the nail group. At the 1-year followup mobility of the knee was on average 110 degrees in the plate group and 103 degrees in the nail group. The Lysholm-Gillquist score did not show any significant differences between the groups. There were clinically relevant varus or outer rotation deviations in three patients in the plate group and two patients in the nail group. The two minimally invasive implants used were good in terms of technique and outcome for treatment of distal femoral fractures and did not differ significantly for epidemiology, fracture type, conversion procedures, infection rate, malalignments, and subjective and objective findings at the 1-year followup. They were also superior to the condylar plate in terms of infection and axial malalignments.