Aims. Accurate and precise acetabular reaming is a requirement for the press-fit stability of cementless acetabular hip replacement components. The accuracy of reaming depends on the reamer, the reaming technique and the bone quality. Conventional reamers wear with use resulting in inaccurate reaming diameters, whilst the theoretical beneficial effect of ‘whirlwind’ reaming over straight reaming has not previously been documented. Our aim was to compare the accuracy and precision of single use additively-manufactured reamers with new conventional reamers and to compare the effect of different acetabular reaming techniques. Materials and Methods. Forty composite bone models, half high-density and half low-density, were reamed with a new 61 mm conventional acetabular reamer using either straight or ‘whirlwind’ reaming techniques. This was repeated with a 61 mm single use additively-manufactured reamer. Reamed cavities were scanned using a 3D laser scanner with mean diameters of reamed cavities compared using the Mann-Whitney U test to determine any statistically significant differences between groups (p<0.05) [Fig. 1). Results. Reaming errors were significantly higher in low-density bone compared to high-density bone for both reamer types and reaming techniques tested (61.9 mm (SD 0.7) vs 61.4 mm (SD 0.4), respectively; p=0.0045). Whirlwind reaming was significantly more accurate and precise than straight reaming using both conventional (61.3 mm (SD 0.1) vs 62.3 mm (SD 0.4), respectively; p<0.0001) and single use reamers (61.1 mm (SD 0.3) vs 61.7 mm (SD 0.7), respectively; p=0.0058) [Fig. 2]. The novel single use reamer was significantly more accurate than the unused conventional reamer, using both the straight (61.7 mm (SD 0.7) vs 62.4 mm (SD 0.4), respectively; p=0.0011) and whirlwind techniques (61.2 mm (SD 0.3) vs 61.3 mm (SD 0.1), respectively; p=0.0002) [Fig. 3]. Conclusion. This is the first study to our knowledge that has assessed acetabular reaming technique in both low and high density saw bones. Improved reaming accuracy and precision was seen in both devices tested when using the ‘whirlwind’ technique in both high-density and low-density bone models when compared to a straight reaming technique. The single use device assessed reamed a cavity size closer to its stated size (61mm) compared to conventional reamers. Based on this study we suggest using a careful “whirlwind” technique when performing acetabular reaming, and for the surgeon to pay particular attention when performing joint replacement in patients with reduced bone quality as there is likely to be more variability in acetabular reaming accuracy in these patients

Introduction: Revision hip implants have poorer clinical outcome than primary implants. The fixation of the implants is often compromised by the formation of an endosteal sclerotic bone rim during the process of aseptic loosening. The cracking procedure is a bone sparing, low energy surgical technique which produces a controlled local perforation of the sclerotic bone rim. In previous studies, we showed that fixation of revision implants significantly improved by the cracking technique for both titanium (Ti) and hydroxyapatite (HA) coated implants (. 1. ). In this study we compared the cracking technique with the common technique of reaming, which completely removes the sclerotic bone rim. Methods: A paired animal study (n=10), in which revision cavities was created by 20 micromotion implant systems inserted in both knees. Micromotion was 0.5mm per gait cycle. After 8 weeks revision surgery was performed. Crack revision: The splined crack tool was introduced over the implant piston with firm axial hammer blows. This producing controlled cracking and local perforation of the sclerotic endosteal rim. The tool is a 6.0 mm cylinder fitted with axially spaced 1.1 mm pointed splines (8.2 mm outer diameter). Reaming revision: A flat bottomed reamer was inserted over the implant piston using one rotation per second. The outer diameter was 8.2 mm in order to remove the sclerotic bone rim. Stable revision Ti implants was inserted. Observation period was 4 weeks. Mechanical push-out tests were performed. Students’ paired t-test was used. Data presented as mean and SEM. Results: Shear strength was markedly higher with the cracking procedure 1.33± 0.3MPa vs. 0.34 ± 0.2 MPa (p< 0.05). Similar results was seen for Stiffness 6.7± 2.0 vs. 1.6 ± 0.9 (p< 0.05) in favor of the cracking procedure. A non-significant increase was seen in energy absorption 170± 47 vs. 50± 29 (p=0.07). Discussion: The cracking procedure improves the mechanical fixation of Ti revision implants compared to a reaming procedure. Shear strength and stiffness was consistently higher for all implant pairs. We have previously shown that the sclerotic bone rim is a barrier for bone ingrowth and that implants inserted with an intact sclerotic bone rim will have a poor biomechanical fixation. Additionally, revision implants inserted with the cracking technique obtained a mechanical fixation comparable to primary implants. Reaming procedures are often used in hip revision surgery. However, as loss of bone stock is a common feature of revision cavities, the reaming procedure may not always be an optimal preparation method of the bone. Excessive removal of bone by reaming may compromise the long term implant stability or increase the risk of peri-implant fractures. The cracking technique may be an alternative or supplemental procedure to reaming

Purpose of the study: Classically, bone grafts are harvested from the iliac crests which can provide a limited volume of graft material. Using the reaming product might help spare iliac bone. Material and method: A variable head RIA device (reaming, irrigation, aspiration) was used over the last year for ten patients who presented partial or segmental bone loss. The bone graft was constructed exclusively with the reaming produce following membrane induction using a cement scaffold. The tibia was reconstructed in nine cases and the humerus in one. Bone loss was 6 cm on average. Results: The reconstruction healed in six cases within a mean delay of 6 months; the 4 other cases are under assessment. Complementary bone was necessary to achieve healing in one case. There were no complications involving the donor site excepting transient pain at the point of insertion. Discussion: In this series associating an induced membrane and reaming produce, the time to healing appeared to be shorter than with cancellous iliac bone. The smaller size of the fragment may be a determining factor. Conclusion: Reaming products collected from medullary cavities of the long bones can be used for reconstruction of bone loss

Patients with a femoral shaft fracture requiring intra-medullary nailing were recruited to investigate if the femoral canal could be a potential source of inflammatory cytokines, previously implicated in the pathogenesis of life-threatening inflammatory complications. Femoral and peripheral blood samples were obtained at the time of surgery from patients with a femoral shaft fracture requiring intramedullary nailing. The local femoral intramedullary and peripheral release of a group of ten Th1 and Th2 cytokines concentrations (IL-1b, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, GM-CSF, TNF-a and IFN-g) after femoral shaft fracture and intramedullary reaming, if performed, was measured using a Human Cytokine Antibody 10-plex Bead Kit. A control group of patients(n=3) undergoing hip replacement was established to allow comparison with the normal femoral intramedullary cytokine environment. 21 patients with a femoral shaft fracture were recruited. Femoral shaft fracture caused a significant increase in the local femoral concentrations of IL-6 (median 3967pg/ml; range 128–25,689pg/ml) and IL-8 (median 238pg/ml; range 8–8,288pg/ml) compared to the femoral control group(p=0.0005 and p=0.001 respectively). No significant local femoral release of the other cytokines was demonstrated. In the patients who underwent intramedullary reaming of the femoral canal (n=6), a further significant local release of IL-6 (median post-ream 15,903pg/ml; range 1,854–44,922pg/ml) and IL-8 (median post-ream 1,443pg/ml; range 493–3,734pg/ml) was demonstrated (p=0.01 and p=0.03 respectively), thus showing that intramedullary reaming can cause a significant local inflammatory response. Femoral shaft fracture produces a local inflammatory response releasing large amounts of the cytokines IL-6 and IL-8 into the local femoral environment but not of the other Th1 and Th2 cytokines studied. Reaming, produced significant elevation in local femoral IL-6 and IL-8 concentration, suggesting a local femoral response as a result of this procedure. Possibly, local femoral environment may act as a cell-priming or stimulating zone, for circulating inflammatory cells

Aims. One goal of total hip arthroplasty is to restore normal hip anatomy. The aim of this study was to compare displacement of the centre of rotation (COR) using a standard reaming technique with a technique in which the acetabulum was reamed immediately peripherally and referenced off the rim. Patients and Methods. In the first cohort the acetabulum was reamed to the floor followed by sequentially larger reamers. In the second cohort the acetabulum was only reamed peripherally, starting with a reamer the same size as the native femoral head. Anteroposterior pelvic radiographs were analysed for acetabular floor depth and vertical and horizontal position of the COR. Results. Horizontally, the mean medial displacement of the COR was 0.8 mm (standard deviation (. sd. ) 1.4) in the peripheral remaing group and 5.0 mm (. sd. 3.30) in the standard reaming group (p < 0.001). Vertically, the mean superior displacement of the COR was 0.7 mm (. sd. 1.3) in the peripheral reaming group and 3.7 mm (. sd. 2.6) in the standard reaming group (p <  0.001). In the standard reaming group, there was a strong correlation between the pre-operative acetabular floor depth and displacement of the COR (p < 0.001). Conclusion. Reaming the acetabulum to the floor can lead to significant displacement of the COR medially and superiorly. This displacement is related to the pre-operative acetabular floor depth and cannot always be compensated by using a high offset stem. Cite this article: Bone Joint J 2016;98-B:1597–603

Purpose: Reaming is classically contraindicated for open leg fractures. For certain authors, reaming can favour bone healing without increasing the risk of infection (Court-Brown JBJS 90B and 91B, Wiss Coor 95). The aim of this retrospective analysis of patients treated in a single centre was to validate these notions and determine the role of locked centromedullary nailing (LN) with reaming for the treatment of open leg fractures. Material and methods: Between 1989 and June 2000, 141 open leg fractures were fixed with locked centromedullary nailing without reaming in 103 men and 38 women, mean age 34 years, who were mainly accident victims (2-wheel vehicles 43%, 4-wheel vehicles 22%). Multiple trauma was present in 18.7% of the cases and multiple fractures in 28%. Skin wounds were (Gustilo classification): type I 81 (57%), type II 38 (27%), type IIIA 14, and type IIIB 8. There was a simple fracture in 50% of the cases, a wedge fracture in 32%, and comminution in 18% with bifocal fractures in 10 cases. Osteosynthesis was performed within a mean 5.5 hours (2–18) and deferred in six cases. The Grosse and Kempf nail was used in all cases with reaming (man 11). Static locking was used in 88% of the cases. type I, II and IIA skin wounds were sutured after debridement. Three aponeurotomies were performed as preventive measures. Type IIIB wounds were treated by early plasty. A brief antibiotic prophylaxis was given in all cases. Results: There was one aggravation of the comminution, two dismantelings subsequent to unauthorised weight-bearing, three compartment syndromes and one lateral sciatic popliteal paralysis. Two patients died from their multiple injuries. Four patients developed infection: two healed without removing the nail, one was amputated (free flap failure). One patient consulted another unit. Ten patients who were not residents of our area were lost to follow-up. Dynamisation was performed in 31 patients (25.6%) at a mean 4.4 months. Four patients with delayed healing cured after a new nailing with secondary reaming. Delay to bone healing was related to the type of fracture (p < 0.01): 4.2 months for type A (AO classification), 5.2 months for type B and 5.9 months for type C. Bone healing was correlated with Gustilo type (p < 0.05): 4.5 months for types I, 4.6 months for type II, 5.8 months for types III. Six patients developed nonunion: four were revised with success after a new nailing and secondary reaming (two lost to follow-up). Delayed healing and non-union were related to type of fracture (A = 3.8%, B = 15.6%, C = 18%) and soft tissue damage (Gustilo I: 4.1%; II: 10.7%; III: 15.8%). Discussion conclusion: Locked centromedullary nailing with reaming is appropriate when the skin wound is minimal; dynamisation and/or replacement of the nail with secondary reaming should be discussed early in case of delayed healing

Aim: To report on the bone histology of patients undergoing intramedullary stabilisation for a pathological fracture or a metastatic lesion in long bones. Materials and methods: From 1999 to 2002, 36 long bones in 29 patients (seven had stabilisation of two long bones) were stabilised with an intramedullary nail in patients with a known primary tumour. Prophylactic fixation was performed in 19 bones with metastatic tumour and in 17 for a fracture. Of the 17 fractures, 13 were considered pathological and four were simple fracture unrelated to metastasis. Thirty-three nailings were done for proximal femoral lesions and three were for the humerus. Reaming samples were sent for histological analysis. The various sites of the primary tumour were Breast (13), Myeloma (6), Prostate (5), Lung (4), Unknown (3), Bladder (2), Oesophagus (1), Renal (1), Melanoma (1). The histological results were correlated with the clinical diagnosis. Results: Thirty-six reaming samples were sent for histological analysis. Twenty-two samples correlated with the clinical diagnosis. Of the 22 tissue samples, two did not have a initial confirmed histological diagnosis of primary and the reaming samples helped to achieve this. Fourteen biopsies gave false negative results. Conclusion: Approximately two-thirds of the time the reaming sample has correlated with clinical diagnosis. Sensitivity of this test is 61%

Introduction: Intramedullary reaming has its selected indication in osteomyelitis of long bones when remnants of dead infected bone are intramedullary embedded in a endostal new bone formation. The validity of this method has not yet been proven in long-term follow-ups. We reevaluated our patients in a 10 to 15 years follow-up to look at the recurrence rate of osteomyelitis after intramedullary reaming. We were also interested in the level of activity and the ability of working in our patients today. Study design: From 1984 till 1992 forty-three patients with forty-four locations of chronic osteomyelitits of long bones were treated by intramedullary reaming. The collective consisted of 38 men and 5 women. The mean duration of the infection was 13.2 years. The causes of osteomyelitis were in 37 cases posttraumatic, in 6 cases haematogenous and one patient suffered from chronic osteomyelitis after removal of a total hip. Main locations of the focus were the diaphysis of the tibia and the femur. Intramedullary reaming was performed in patients with a infection centrally located in the bone protected by a thick periosteal new bone formation. In important endosteal bone formation a window was needed in order to pass with the guide wire for medullary reaming. Reaming went up to 18mm leaving a important cortical thickness of 6 to 10mm. Thorough irrigation focused a total removal of reaming mill. The treatment included a antibiotic therapy from 6 to 12 weeks. Staph. aureus was the most frequent micro-organism. The follow-up data was based on a continously documented clinical observation. Next to visits in our outpatient clinic we received informations by having designed a questionnaire booklet which was answered by the patients. Results: In the 10 year follow-up in 37 cases (83%) osteomyelitis had never reoccurred. 5 patients needed a revision. 23 patients worked full-time, 3 had a reduced ability of work and 8 had been retired. 27 patients were pain-free, in 7 cases mild pain was found and 1 patient had moderate pain during working or walking. We have reevaluted 21 patients in a 15years follow-up, 7 patients will be followed up by 10/2004. Fifteen patients had died. Discussion: Intramedullary reaming of the diaphysis of long bones after posttraumatic or haematogenous osteomyelitis proves to be a valuable treatment. The constitution of the bone, the reaming technique and the antibiotic therapy are influencing factors for a positive outcome

Introduction

Total hip arthroplasty (THA) is one of the most common orthopedic surgeries. The procedure is sophisticated and in addition to several factors affecting the outcomes such as patient's status, surgeon's expertise and implant type, using appropriate surgical tools is necessary. Acetabular component implantation necessitates the surgeon to ream the acetabular fossa which is time consuming and devastating. Utilizing currently-used reamers (figure 1), the size of the tool must be changed repeatedly for 5–20 times within a surgery. In every stage, the size of the reamer is increased up to 1–2 mm. This tiring process takes 15–30 minutes and is associated with some injuries to the soft tissue. Furthermore, the risk of mistakes is considerable.

Introduction

Primary stability is achieved by the press fit technique, where an oversized component is inserted into an undersized reamed cavity. The major geometric design of an acetabular shell is hemispherical type. On the other one, there are the hemielliptical type acetabular shells for enhanced peripheral contact.

In the case of developmental dysplasia of the hip (DDH), the aseptic loosening may be induced by instability due to decreased in the contact area between the acetabular shell and host bone.

The aim of this study was to assess the effect of reaming size on the primary stability of two different outer geometry shells in DDH models.

INTRODUCTION:

Recent trends in total hip arthroplasty (THA) have resulted in the use of larger acetabular components to achieve larger femoral head sizes to reduce dislocation, and improve range of motion and stability. Such practices can result in significant acetabular bone loss at the time of index THA, increasing risk of anterior/posterior wall compromise, reducing component coverage, component fixation, ingrowth surface and bone stock for future revision surgery. We report here on the effects of increasing acetabular reaming on component coverage and bone loss in a radiographic CT scan based computer model system.

Total Shoulder Resurfacing (TSR) provides a reliable solution for the treatment of glenohumeral arthritis. It confers a number of advantages over traditional joint replacement with stemmed humeral components, in terms of bone preservation and improved joint kinematics.

This study aimed to determine if humeral reaming instruments produce a thermal insult to subchondral bone during TSR. This was tested in vivo on 13 patients (8 with rheumatoid arthritis and 5 with osteoarthritis) with a single reaming system and in vitro with three different humeral reaming systems on saw bone models. Real-time infrared thermal video imaging was used to assess the temperatures generated.

Synthes Epoca instruments generated average temperatures of 40.7°^C (SD 0.9°^C) in the rheumatoid group and 56.5°^C (SD 0.87°^C) in the osteoarthritis group (p = 0.001). Irrigation with room temperature saline cooled the humeral head to 30°^C (SD 1.2°^C). Saw bone analysis generated temperatures of 58.2°^C (SD 0.79°^C) in the Synthes (Epoca) 59.9°^C (SD 0.81°^C) in Biomet (Copeland) and 58.4°^C (SD 0.88°^C) in the Depuy (CAP) reamers (p=0.12).

Humeral reaming with power driven instruments generates considerable temperatures both in vivo and in vitro. This paper demonstrates that a significant thermal effect beyond the 47°^C threshold needed to induce osteonecrosis is observed with humeral reamers, with little variation seen between manufacturers. Irrigation with room temperature saline cools the reamed bone to physiological levels, and should be performed regularly during this step in TSR.

Retroversion, also referred to as posterior wear of the glenoid, can make resurfacing the glenoid challenging. However, careful pre-operative planning with three dimensional CT scanning can allow central placement of the glenoid component through removal of some of the anterior bone to allow contained placement and secure fixation within the glenoid vault.

Since the scapula is not a fixed skeletal structure and moves substantially on the chest wall, the actual degree of posterior wear (retroversion) frequently is the result of extraneous biomechanical forces and structures. For example, the degree of kyphosis and shape of the rib cage can have a substantial impact on the relative position of the glenoid surface as it articulates with the humerus. Attempts to totally equalise this through implant augmentation have not, to date, been shown to be effective, and in some cases can be destabilising. Restoration of enough alignment to place the implant centrally can be achieved without need for augmentation even in some very hypoplastic glenoids. The technique for this straight-forward approach will be presented, including pre-surgical planning, in some cases, patient specific instrumentation, with demonstration of functional outcomes.

Contracture of the anterior musculature causes posterior humeral head subluxation and results in a posterior load concentration on the glenoid. This reduced contact area causes glenoid wear, humeral medialisation and eventually posterior instability. After arthroplasty that does not correct for this, posterior wear stress increases in the implant, across the cement mantle and bone thus increasing the risk of aseptic loosening over time.

Correction of the posterior wear pattern at the time of arthroplasty of the shoulder is recommended. Asymmetric reaming of the glenoid has been recommended as a means to correct this deformity but leads to producing a smaller glenoid which is medialised. This shortening of the glenoid causes the stabilising muscle envelope to shorten and the glenoid vault to become much smaller in volume. These potential changes may have a destabilising effect on the implant leading to early loosening and secondary failure of the prosthetic implant.

Other options include using an implant to make the correction of the deformity such as augmented glenoid components. Early uses of these implants were not successful mainly due to the design flaws of the early implants. Newer implants have made design changes to overcome these early failures. CT scan evaluation is important to determine the degree of correction that is needed to balance the glenohumeral joint. Correcting the deformity and keeping the muscle envelope at the appropriate tension may lead to better long term outcomes. These implants are currently in use but long term outcome studies are not yet available to determine their ultimate values to the patients.

Purpose: The purpose of this study was to relate the extent of reaming to bone formation occurring around a critical sized defect in the tibia.

Method: Eleven canines were allocated into 2 groups: empty (N=5) or iliac crest autograft (N=6). All tibiae were reamed to 7.0 mm and fixed with a 6.5 mm statically locked intramedullary nail after creation of an 8.0 mm diaphyseal defect. The extent of reaming of the canal was dependent on the cross-sectional area of the tibia as all tibiae were reamed to 7.0 mm. Fluorescent markers were given at different times: calcein green (6 weeks), xylenol orange (9 weeks), and tetracycline (11 and 14 weeks). Animals were sacrificed at 15 weeks and perfused with a barium compound. Radiography, Micro CT, brightfield microscopy and fluorescent microscopy were used for analysis.

Results: Bone and vasculature volume within the defect were reported as a percentage of the total volume of the defect. Linear regression analysis of percent bone volume (dependent variable) and canal area (independent variable) provided a Pearson correlation coefficient of 0.925 (p=0.025) for the empty group and 0.244 (p=0.641) for the autograft group. Linear regression analysis of percent vasculature volume (dependent variable) and canal area (independent variable) provided a Pearson correlation coefficient of 0.784 (p=0.117) for the empty group and −0.146 (p=0.783) for the autograft group. Bone formation at osteotomy sites was defined as the distance from the original osteotomy site to the tip of newly formed bone. Linear regression analysis of bone formation at the osteotomy sites (dependent variable) and canal area (independent variable) provided a Pearson correlation coefficient of 0.132 (p=0.832) for the empty group and −0.937 (p=0.006) for the autograft group. Bone formation rates were reported as the distance between the fluorescent labels. Bone formation rate was less within the endosteum, cortex and periosteum with extensive reaming in empty samples.

Conclusion: Our results suggest that the acute management of tibia fractures with bone defects should involve limited reaming. This does not apply when the defect is autografted. Limited reaming may be defined by the cross-sectional area of the tibia in ratio to that of the reamer.

Introduction

Proper femoral reaming is a key factor for a successful outcome in cementless hip arthroplasty. Good quality reaming minimizes risks of intra-operative femoral fracture during reaming and prevents poor fitting of the implant which can lead to subsidance of the stem postoperativly. Determining the quality of reaming is largely a subjective skill and dependant on the surgeon's experience with no documented intraoprative method to assess it objectively.

We present three young men who sustained closed diaphyseal fracture of the tibia and later developed severe osteocutaneous necrosis induced by heat during intramedullary reaming. They all had a narrow medullary cavity and in all a tourniquet had been used. Each developed a pretibial cutaneous blister soon after operation. In the following month severe osteomyelitis ensued, requiring segmental resection and osteocutaneous reconstruction.

Hip resurfacing has many advantages such as proximal bone conservation and easy revision including conversion to total hip arthroplasty. The major complication in the hip resurfacing is notching at the lateral cortical bone and fracture of the neck. In this research, we simulated the range of direction of reaming without causing notch.

One left femur model was used for the simulation. The femoral head was fitted by a sphere and the origin of Cartesian coordinate was set at the center of the sphere. The simulation was made by imposing a cylindrical cut to the femoral head in varying direction and location. The existence of notching was decided comparing the maximum distance from reaming axis to neck section contour and the radius of cylindrical cut. If the maximum distance is bigger than the radius of cut, the notching exists and vice versa. We simulated existence of notching by varying inclination(α) from 20 to 70 degrees, anteversion(β) from 0 to 30 degree and depth passing through the head center(d) from 0 to 5mm. The implant used for the simulation was Durom^®, Zimmer^©. We selected the implant size that is close to the fitted sphere of femoral head.

No notching was made for any direction when the depth d was less than 2mm. When the depth was 3mm, notching did not generate in the range of α from 43 degrees to 60 degrees and β from 0 to 25 degrees. When the range of depth was from 4mm to 5mm, notching did not generate in ranges of α from 41 degrees to 60 degrees and β from 0 to 29 degrees. The no-notching angle range had tendency increasing slightly when the depth was increased. The angle between the stem of the implant and the neck shaft axis without notching can be calculated from the angle α. When the depth was from 4mm to 5mm, the corresponding angle between stem of implant and the shaft axis was from 120 degrees to 139 degrees.