Aims. The aim of this prospective randomised controlled trial was to compare non-operative and operative management for acute isolated displaced fractures of the olecranon in patients aged ≥ 75 years. Patients and Methods. Patients were randomised to either non-operative management or operative management with either tension-band wiring or fixation with a plate. They were reviewed at six weeks, three and six months and one year after the injury. The primary outcome measure was the Disabilities of the Arm, Shoulder and Hand (DASH) score at one year. Results. A total of 19 patients were randomised to non-operative (n = 8) or operative (n = 11; tension-band wiring (n = 9), plate (n = 2)) management. The trial was stopped prematurely as the rate of complications (nine out of 11, 81.8%) in the operative group was considered to be unacceptable. There was, however, no difference in the mean DASH scores between the groups at all times. The mean score was 23 (0 to 59.6) in the non-operative group and 22 (2.5 to 57.8) in the operative group, one year after the injury (p = 0.763). There was no significant difference between groups in the secondary outcome measures of the Broberg and Morrey Score or the Mayo Elbow Score at any time during the one year following injury (all p ≥ 0.05). . Conclusion. These data further support the role of primary non-operative management of isolated displaced fractures of the olecranon in the elderly. However, the non-inferiority of non-operative management cannot be proved as the trial was stopped prematurely. Cite this article: Bone Joint J 2017;99-B:964–72

The aim of this study was to document both the short and long term outcome of isolated displaced olecranon fractures treated with primary non-operative intervention. We identified from our prospective trauma database all patients who were managed non-operatively for a displaced olecranon fracture over a 13-year period. Inclusion criteria included all isolated fractures of the olecranon with >2 mm displacement of the articular surface. Demographic data, fracture classification, management, complications and subsequent surgeries were recorded. The primary short-term outcome measure was the Broberg and Morrey Elbow score. The primary long-term outcome measure was the DASH score. There were 43 patients in the study cohort with a mean age of 76 yrs (40–98). A low energy fall from standing height accounted for 84% of all injuries, with ≥1 co-morbidities documented in 38 (88%) patients. At a mean of 4 months (range, 1.5–10) following injury the mean Broberg and Morrey score was 83 (48–100), with 72% achieving an excellent or good short-term outcome. Long-term follow-up was available in 53% (n=21) patients, with the remainder deceased. At a mean of six years (2–15) post injury, the mean DASH score was 2.9 (0–33.9), the mean Oxford Elbow Score was 47 (42–48) and overall patient satisfaction was 91% (n=21). We have reported satisfactory short-term and longer-term outcomes following the non-operative management of isolated displaced olecranon fractures in older lower demand patients. Further work is needed to directly compare operative and non-operative management in this patient group

To assess the stability of the hip after acetabular fracture, dynamic fluoroscopic stress views were taken of 41 acetabular fractures that met the criteria for non-operative management. These included roof arcs of 45°, a subchondral CT arc of 10 mm, displacement of less than 50% of the posterior wall, and congruence on the AP and Judet views of the hip. There were three unstable hips which were treated by open reduction and internal fixation. The remaining 38 fractures were treated non-operatively with early mobilisation and delayed weight-bearing. At a mean follow-up of 2.7 years, the results were good or excellent in 91% of the cases. Three fair results were ascribed to the patients’ other injuries. Dynamic stress views can identify subtle instability in patients who would normally be considered for non-operative treatment

Limited long term data exists comparing operatively and non-operatively treated Achilles tendon ruptures. A previous randomised controlled trial comparing early outcomes showed a short term advantage for surgery, but there are no long term prospective randomised comparisons. Our aim was to determine whether surgery conferred long term benefits in terms of patient reported outcomes or re-rupture. 64 patients (80%) were followed up with postal questionnaires. Patients were asked to complete the Short Musculoskeletal Function Assessment (SMFA), Achilles Tendon Total Rupture Score (ATRS) and EQ-5D questionnaires, and to report re-ruptures. 32 patients were treated non-operatively and 32 operatively; 59 completed the SMFA and 64 the ATRS and EQ-5D assessments. There was no significant difference in SMFA score (median 1.09, IQR 4.89 in the cast group versus 2.17 and 7.07 in the operative group; p=0.347), ATRS (median 96, IQR 18 versus 93 and 15; p=0.509), EQ-5D Index (median 1.0, IQR 0.163 versus 1.0 and 0.257; p=0.327) and EQ-5D Visual Analogue Score (median score 85, IQR 15 versus 85 and 24; p=0.650). There were 2 re-ruptures in the operative group and 4 in the non-operative group (p=0.067). This is the first prospective, randomised, long term report comparing operative and non-operative management. At follow up between 13–17 years after injury, patients reported good function and health related quality of life. There was no significant difference in re-rupture rate between the treatment groups

Background. Primary dislocation of the patella is a common acute knee disorder in children, adolescents and young adults. While primary dislocation of the patella has traditionally been treated non-operatively, primary operative repair of the medial patella-stabilizing soft tissues has been popularized more recently and thought to reduce the risk of dislocation. However, several studies have shown substantial rates of redislocation with longer follow-up time, irrespective of treatment. The purpose of this systematic review was to compare operative and non-operative treatment for primary dislocation of the patella, regarding redislocation rates and symptoms. Methods. Based on a systematic literature search of the medical literature from 1950 to 2010, three randomized and two quasi-randomized controlled clinical trials comparing surgical stabilization with non-operative treatment for patients with primary patellar dislocation were selected. The Risk of Bias Tool (Cochrane Handbook, 2008) was used to assess the quality of the studies included. Study results were pooled using the fixed-effects and random-effects models with mean differences and risk ratios for continuous and dichotomous variables, respectively. Heterogeneity across studies was assessed with Q test and I-square statistic. A sensitivity analysis was performed by assessing the change on effect size by eliminating each single trial. Results. In total, 341 patients from 5 trials were included. 158 patients were treated non-operatively and 183 patients were treated operatively. For primary outcome of patellar redislocation, while significant heterogeneity was found using the random-effects model, no significant difference was observed between the treatment groups (pooled RR=1.36, 95% CI 0.8–2.31, p=0.25). No significant difference was observed between the treatment groups (pooled RR=1.36, 95% CI0.8–2.31, p=0.25). No significant differences were found between both groups for symptoms ofinstability (RR of 1.24, 95% CI 0.96–1.59, p=0.10), Kujala knee score (−5.66, 95% CI −15.51 −4.19, p=0.26) or requirement for later surgery (RR=0.92, CI 0.61–1.39, p=0.69). Conclusions. This meta-analysis found no differences in patellar redislocation rate, patient reported instability symptoms, Kujala Knee score and rate of later surgery after initial treatment, between operative and non-operative treatment of primary patellar dislocation. Level of evidence. Level II

Aims

The aims of this network meta-analysis (NMA) were to examine nonunion rates and functional outcomes following various operative and nonoperative treatments for displaced mid-shaft clavicle fractures.

Aims

The PROximal Fracture of the Humerus Evaluation by Randomisation (PROFHER) randomised clinical trial compared the operative and non-operative treatment of adults with a displaced fracture of the proximal humerus involving the surgical neck. The aim of this study was to determine the long-term treatment effects beyond the two-year follow-up.

This study aimed to evaluate the effect of clavicular shortening, measured by three-dimensional computerized tomography (3DCT), on functional outcomes and satisfaction in patients with healed, displaced, midshaft clavicle fractures up to one year following injury.

The data used in this study were collected as part of a multicenter, prospective randomized control trial comparing open reduction and plate fixation with nonoperative treatment for displaced midshaft clavicle factures. Patients who were randomized to nonoperative treatment and who had healed by one year were included. Clavicle shortening relative to the uninjured contralateral clavicle was measured on 3DCT. Outcome analysis was conducted at six weeks, three months, six months and one year following injury and included the Disabilities of the Arm, Shoulder and Hand (DASH), Constant and Short Form-12 (SF-12) scores, and patient satisfaction.

48 patients were included. The mean shortening of injured clavicles, relative to the contralateral side, was 11mm (+/− 7.6mm) with a mean proportional shortening of 8percnt;. Proportional shortening did not significantly correlate with the DASH (p>0.42), Constant (p>0.32) or SF-12 (p>0.08) scores at any time point. There was no significant difference in the mean DASH or Constant scores at any followup time point both when the cut off for shortening was defined as one centimeter (p>0.11) or two centimeters (p>0.35). There was no significant difference in clavicle shortening between satisfied and unsatisfied patients (p>0.49).

This study demonstrated no association between shortening and functional outcome or satisfaction in patients with healed, displaced, midshaft clavicle fractures up to one year following injury.

The generally-accepted treatment for large, displaced fractures of the glenoid associated with traumatic anterior dislocation of the shoulder is operative repair. In this study, 14 consecutive patients with large (> 5 mm), displaced (> 2 mm) anteroinferior glenoid rim fractures were treated non-operatively if post-reduction radiographs showed a centred glenohumeral joint.

After a mean follow-up of 5.6 years (2.8 to 8.4), the mean Constant score and subjective shoulder value were 98% (90% to 100%) and 97% (90% to 100%), respectively. There were no redislocations or subluxations, and the apprehension test was negative. All fragments healed with an average intra-articular step of 3.0 mm (0.5 to 11). No patient had symptoms of osteoarthritis, which was mild in two shoulders and moderate in one.

Traumatic anterior dislocation of the shoulder, associated with a large displaced glenoid rim fracture can be successfully treated non-operatively, providing the glenohumeral joint is concentrically reduced on the anteroposterior radiograph.

This single-centre prospective randomised trial aimed to assess the superiority of operative fixation compared with non-operative management for adults with an isolated, closed humeral shaft fracture. 70 patients were randomly allocated to either open reduction and internal fixation (51%, n=36/70) or functional bracing (49%, n=34/70). 7 patients did not receive their assigned treatment (operative n=5/32, non-operative n=2/32); results were analysed based upon intention-to-treat. The primary outcome measure was the DASH score at 3 months. Secondary outcomes included treatment complications, union/nonunion, shoulder/elbow range of motion, pain and health-related quality of life (HRQoL). At 3 months, 66 patients (94%) were available for follow-up; the mean DASH favoured surgery (operative 24.5, non-operative 39.4; p=0.006) and the difference (14.9 points) exceeded the MCID. Surgery was also associated with a superior DASH at 6wks (operative 38.4, non-operative 53.1; p=0.005) but not at 6 months or 1yr. Brace-related dermatitis affected 7 patients (operative 3%, non-operative 18%; OR 7.8, p=0.049) but there were no differences in other complications. 8 patients (11%) developed a nonunion (operative 6%, non-operative 18%; OR 3.8, p=0.140). Surgery was associated with superior early shoulder/elbow range of motion, and pain, EuroQol and SF-12 Mental Component Summary scores. There were no other differences in outcomes between groups. Surgery confers early advantages over bracing, in terms of upper limb function, shoulder/elbow range of motion, pain and HRQoL. However, these benefits should be considered in the context of potential operative risks and the absence of any difference in patient-reported outcomes at 1yr

The primary aim was to estimate the cost-effectiveness of routine operative fixation for all patients with humeral shaft fractures. The secondary aim was to estimate the cost-effectiveness of using a Radiographic Union Score for HUmeral fractures (RUSHU)<8 to facilitate selective fixation for patients at risk of nonunion. From 2008-2017, 215 patients (mean age 57yrs [17–81], 61% female) with a non-operatively managed humeral diaphyseal fracture were retrospectively identified. Union was achieved in 77% (n=165/215) after non-operative management, with 23% (n=50/215) uniting after nonunion surgery. The EuroQol Five-Dimension (EQ-5D) Health Index was obtained via postal survey. An incremental cost-effectiveness ratio (ICER) <£20,000 per quality-adjusted life-year (QALY) gained was considered cost-effective. At a mean of 5.4yrs (1.2–11.0), the mean EQ-5D was 0.736. Multiple regression demonstrated that uniting after nonunion surgery was independently associated with an inferior EQ-5D (beta=0.103, p=0.032). Routine fixation for all patients to reduce the nonunion rate would be associated with increased treatment costs (£1,542/patient) but confer a potential EQ-5D benefit of 0.120/patient. The ICER of routine fixation was £12,850/QALY gained. Selective fixation, based upon a RUSHU<8 at 6wks post-injury, would be associated with reduced treatment costs (£415/patient) and confer a potential EQ-5D benefit of 0.335 per ‘at-risk patient’. Routine fixation for patients with humeral shaft fractures, to reduce the nonunion rate observed after non-operative management, appears to be cost-effective at 5yrs post-injury. Selective fixation for patients at risk of nonunion based upon the RUSHU may confer greater cost-effectiveness, given the potential savings and improvement in EQ-5D

This study aimed to assess the outcomes of patients with complex rib fractures undergoing operative or non-operative management at our center over a six-year time period. Retrospective analysis was performed to identify all patients with complex rib fractures at our center from May 2016 to September 2022. Outcome measures included mechanical ventilation, tracheostomy, pneumonia, and mortality at one year. 388 patients with complex rib fractures were identified. 37 (10%) patients fulfilled criteria for surgical management and underwent rib fracture fixation; 351 patients were managed non-operatively with anaesthetic block or analgesia alone. The fixation group had a significantly higher proportion of patients with flail chest (30 (81%) vs 94 (27%), p<0.001) and were significantly more likely to require ICU admission (30 (81%) vs. 16 (5%), p<0.001) than the non-operative group. At one year follow-up, no significant differences were seen for mortality between these groups (1 (3%) vs. 27 (7%), p=0.276). Of the surgical management group, those that underwent fixation <72 hours post injury were significantly less likely to develop pneumonia than those who were delayed >72 hours (2 (18%) vs 15 (58%), p=0.038), with downward trends noted for ICU length of stay (6 vs 10 days, p=0.140) and duration of mechanical ventilation (5 vs 8 days, p=0.177); no significant differences were seen for tracheostomy (3 vs. 5, p=0.588) or mortality (0 vs 1, p=0.856). Surgical fixation of complex rib fractures improves outcomes in selected patient groups. Early surgical fixation led to reduced rates of pneumonia and may improve other outcome measures

The aim of this study was to define the long-term outcome following adolescent clavicle fracture. We retrospectively reviewed all adolescent fractures presenting to our region (13–17years) over a 10-year period. Patient reported outcomes were undertaken at a minimum of 4 years post-injury (QuickDASH and EQ-5D) in completely displaced midshaft fractures (Edinburgh 2B, >2cm displacement, n=50) and angulated midshaft fractures (Edinburgh 2A2, >30 degrees angulation, n=32). 677 clavicle fractures were analysed. The median age was 14.8 (IQR 14.0–15.7) and 89% were male. The majority were midshaft (n=606, 89.5%) with either angulation (39.8%) or simple fully displaced (39.1%). Only 3% of midshaft fractures underwent acute fixation (n=18/606), all of which were fully displaced. The incidence of refracture following non-operative management of midshaft fractures was 3.2% (n=19/588), all united with non-operative management. Fracture type, severity of angulation or displacement was not associated with risk of refracture. There was one case of non-union encountered following non-operative management of all displaced midshaft fractures (0.4%, n=1/245). At a mean of 7.6 years following injury, non-operative management of both displaced and angulated fractures had a median QuickDASH was 0.0 (IQR 0.0–2.3), EQ-5D was 1.0 (IQR 1.0–1.0). 97% of angulated fractures and 94% of displaced fractures were satisfied with their final shoulder function. We conclude that Non-operative management of adolescent midshaft clavicle fractures result in excellent functional outcomes with a low rate of complications at long-term follow up. The relative indications for surgical intervention for clavicle fractures in adults do not appear to be applicable to adolescents

Non-operative management of displaced olecranon fractures in elderly low demand patients is reported to result in a satisfactory outcome despite routinely producing a nonunion. The aim of this study was to assess whether there is evidence of dynamic movement of the fracture fragment during the elbow arc of movement. Five consecutive patients (≥70 years of age) with a displaced olecranon fracture (Mayo 2A) that were managed with non-operative intervention were recruited. All underwent ultrasound evaluation at six weeks and follow-up questionnaires at six months including the DASH and Oxford Elbow Score (OES). There were three women and two men with a mean age of 79yrs (range 70–88). All injuries were sustained following a fall from standing height. The mean fracture gap in extension was 22.5mm (95% CI 13.0–31.9), midflexion 21.8mm (11.6–32.0) and in deep flexion 21.8mm (10.9–32.8). Although the amount of fracture displacement varied between patients, it remained static in each patient with no significant differences observed throughout the arc of motion (ANOVA p=0.99). The six-month median DASH score was 7.5 (IQR range, 4.2–39.3) and the OES was 44.0 (29.0–47.5). Four out of the five patients were satisfied with their function. Ultrasound evaluation of displaced olecranon fractures following non-operative management suggests the proximal fragment may function as a sesamoid type bone within the triceps sleeve. This could explain how a functional arc of movement with a minimum level of discomfort can usually be expected with non-operative management in select patients

This prospective, randomized, controlled trial compares patient outcome after non-operative care versus open reduction and tunneled suspension device fixation (ORTSD) for grade III or IV acromioclavicular joint disruptions. Sixty patients aged between sixteen and thirty-five years with an acute grade III or IV AC joint disruption were randomized to receive ORTSD fixation or non-operative treatment. Functional assessment was conducted at six weeks, three months, six months, and one year using the Disabilities of the Arm, Shoulder and Hands (DASH), Oxford Shoulder Scores (OSS) and Short Form (SF-12). Reduction was evaluated using radiographs. Complications were recorded, and an economic evaluation performed. There was no significant difference in DASH or OSS at one year between non-operative and ORTSD groups (DASH score, 4.67 versus 5.63; OSS, 45.72 versus 45.63). Patients undergoing surgery had inferior DASH scores at 6 weeks (p<0.01). Five patients who failed non-operative management subsequently received surgery. Overall cost of treatment was significantly greater after ORTSD fixation (£796.22 vs £3359.73 (p<0.01)). ORTSD fixation confers no functional benefit over non-operative treatment at one year. While patients managed non-operatively generally recover faster, a significant group remain dissatisfied following non-operative treatment requiring delayed surgical reconstruction

Aims. Flail chest from a blunt injury to the thorax is associated with significant morbidity and mortality. Its management globally is predominantly non-operative; however, there are an increasing number of centres which undertake surgical stabilisation. The aim of this meta-analysis was to compare the efficacy of this approach with that of non-operative management. Patients and Methods. A systematic search of the literature was carried out to identify randomised controlled trials (RCTs) which compared the clinical outcome of patients with a traumatic flail chest treated by surgical stabilisation of any kind with that of non-operative management. Results. Of 1273 papers identified, three RCTs reported the results of 123 patients with a flail chest. Surgical stabilisation was associated with a two thirds reduction in the incidence of pneumonia when compared with non-operative management (risk ratio 0.36, 95% confidence interval (CI) 0.15 to 0.85, p = 0.02). The duration of mechanical ventilation (mean difference -6.30 days, 95% CI -12.16 to -0.43, p = 0.04) and length of stay in an intensive care unit (mean difference -6.46 days, 95% CI 9.73 to -3.19, p = 0.0001) were significantly shorter in the operative group, as was the overall length of stay in hospital (mean difference -11.39, 95% CI -12.39 to -10.38, p < 0.0001). Conclusion. Surgical stabilisation for a traumatic flail chest is associated with significant clinical benefits in this meta-analysis of three relatively small RCTs. Cite this article: Bone Joint J 2016;98-B:1119–25

The primary aim was to identify patient and injury factors independently associated with humeral diaphyseal fracture nonunion after non-operative management. The secondary aim was to determine the effect of management (operative/non-operative) on nonunion. Over a ten-year period, 734 humeral diaphyseal fractures (732 consecutive patients) were retrospectively identified from a trauma database. Follow-up was available for 663 fractures (662 patients; median age 57yrs [16–96], 54% female [n=359/662]) which formed the study cohort. Patient and injury characteristics were recorded. There were 523 patients (79%) managed non-operatively and 139 (21%) managed operatively. Outcome (union/nonunion) was determined from medical records and radiographs. Median follow-up was five months (1.2–74). Nonunion occurred in 22.7% of non-operatively managed injuries (n=119/524). Multivariate analysis demonstrated pre-injury NSAIDs (adjusted OR [AOR] 40.8, 95% CI 2.6–632.3; p=0.008), being underweight (BMI <18.5kg/m2; AOR 7.3, 95% CI 1.3 to 40.2; p=0.022), overweight (BMI 25–29.9kg/m2; AOR 2.5, 95% CI 1.1 to 5.9; p=0.034) and class II obesity (BMI 35–39.9kg/m2; AOR 4.5, 95% CI 1.4 to 15.5; p=0.014) were independently associated with an increased risk of nonunion. Operative fixation was independently associated with a lower risk of nonunion (2.9%, n=4/139) than non-operative management (AOR for non-operative/operative 11.0, 95% CI 2.8 to 43.6; p=0.001). Based upon these results, five patients would need to undergo operative fixation to avoid one nonunion. Pre-injury NSAIDs and BMI were independently associated with nonunion following non-operative management of a humeral diaphyseal fracture. Operative fixation was the independent factor most strongly associated with a lower risk of nonunion

Management of highly displaced acromioclavicular joint (ACJ) injuries remain contentious. It is unclear if delayed versus acute reconstruction has an increased risk of fixation failure and complications. The primary aim of this was to compare complications of early versus delayed reconstruction. The secondary aim was to determine modes of failure of ACJ reconstruction requiring revision surgery. A retrospective study was performed of all patients who underwent operative reconstruction of ACJ injuries over a 10-year period (Rockwood III-V). Reconstruction was classed as early (<12 weeks from injury) or delayed (≥12 weeks). Patient demographics, fixation method and post-operative complications were noted, with one-year follow-up a minimum requirement for inclusion. Fixation failure was defined as loss of reduction requiring revision surgery. 104 patients were analysed (n=60 early and n=44 delayed). Mean age was 42.0 (SD 11.2, 17–70 years), 84.6% male and 16/104 were smokers. No difference was observed between fixation failure (p=0.39) or deep infection (p=0.13) with regards to acute versus delayed reconstruction. No patient demographic or timing of surgery was predictive of fixation failure on regression modelling. Overall, eleven patients underwent revision surgery for loss of reduction and implant failure (n=5 suture fatigue, n=2 endo-button escape, n=2 coracoid stress fracture and n=2 deep infection). This study suggests that delayed ACJ reconstruction does not have a higher incidence of fixation failure or major complications compared to acute reconstruction. For those patients with ongoing pain and instability following a trial of non-operative treatment, delayed reconstruction would appear to be a safe treatment approach

The primary aim was to determine the rate of complications and re-intervention rate in a consecutive series of operatively managed distal radius fractures. Data was retrospectively collected on 304 adult distal radius fractures treated at our institution in a year. Acute unstable displaced distal radius fractures surgically managed within 28 days of injury were included. Demographic and injury data, as well as details of complications and their subsequent management were recorded. There were 304 fractures in 297 patients. The mean age was 57yrs and 74% were female. Most patients were managed with open reduction and internal fixation (ORIF) (n=278, 91%), with 6% (n=17) managed with manipulation and Kirschner wires and 3% (n=9) with bridging external fixation. Twenty-seven percent (n=81) encountered a post-operative complication. Complex regional pain syndrome was most common (5%, n=14), followed by loss of reduction (4%). Ten patients (3%) had a superficial wound infection managed with oral antibiotics. Deep infection occurred in one patient. Fourteen percent (n=42) required re-operation. The most common indication was removal of metalwork (n=27), followed by carpal tunnel decompression (n=4) and revision ORIF (n=4). Increasing age (p=0.02), male gender (p=0.02) and high energy mechanism of injury (p<0.001) were associated with developing a complication. High energy mechanism was the only factor associated with re-operation (p<0.001). This study has documented the complication and re-intervention rates following distal radius fracture fixation. Given the increased risk of complications and the positive outcomes reported in the literature, non-operative management of displaced fractures should be considered in older patients

A high rate of complications is associated with open reduction and internal fixation of Sanders type 4 fractures of the calcaneum. We assessed the long-term outcome of 83 Sanders type 4 comminuted intra-articular fractures of the calcaneum in 64 patients who underwent non-operative treatment between 1999 and 2005. Each fracture was treated by closed reduction and immobilisation in a long leg cast. Patients were reviewed every three months in the first year, and every six months thereafter. At each visit, the involved ankles were assessed by the American Orthopaedic Foot and Ankle Society (AOFAS) criteria. The degree of fracture healing and the presence of osteoarthritis were assessed. At a mean follow-up of 51 months (24 to 70) the mean AOFAS score was 72 (52 to 92). Osteoarthritis was scored radiologically using Graves’ classification and was evident in the subtalar joints of 75 ankles (90%) on x-ray and in all ankles on CT scans, of which 20 were grade 0 or 1, 39 grade 2, and 24 grade 3. A non-operative approach to treating these fractures may be simpler, less expensive, easier to administer with fewer complications, and may be better tolerated than surgery, by many patients