JBJS welcomes reader comments on published articles. Letters to the Editor are reviewed by JBJS editors but are not peer-reviewed. To submit your letter, please follow the "submit a response" link that appears in the content box at the upper right of the full text of the article.

Letters to the Editor to:

Scientific Articles:
Antonio Moroni, Cesare Faldini, Francesco Pegreffi, Amy Hoang-Kim, Francesca Vannini, and Sandro Giannini
Dynamic Hip Screw Compared with External Fixation for Treatment of Osteoporotic Pertrochanteric Fractures. A Prospective, Randomized Study
J Bone Joint Surg Am 2005; 87: 753-759 [Abstract] [Full text] [PDF]
*Letters to the Editor: Submit a response to this article

Electronic letters published:

[Read Letter to the Editor] A Response by Dr. Moroni to the on line JBJS Commentary and Perspective by Dr. Marsh
Antonio Moroni, M.D.   (26 July 2005)
[Read Letter to the Editor] "Dynamic Hip Screw Compared with External Fixation for Treatment of Osteoporotic Pertrochanteric Fra
Rahij Anwar, N. Gogi, S.A. Khan, A.A., and A.A. Iraqi   (16 June 2005)
[Read Letter to the Editor] External Fixation versus Dynamic Hip Screw for Pertrochanteric Fractures
MANOJ TODKAR   (8 June 2005)
[Read Letter to the Editor] Dr Moroni et al respond to Dr. Todkar
Antonio Moroni, Cesare Faldini, Francesco Pegreffi, Amy Hoang-Kim, Francesca Vannini, Sandro Giannini   (8 June 2005)

A Response by Dr. Moroni to the on line JBJS Commentary and Perspective by Dr. Marsh 26 July 2005
Previous Letter to the Editor Top
Antonio Moroni, M.D.,
Professor of Orthopaedic Surgery
University of Bologna, Rizzoli Orthopaedic Institute, Bologna, Italy

Send letter to journal:
Re: A Response by Dr. Moroni to the on line JBJS Commentary and Perspective by Dr. Marsh

a.moroni{at}ior.it Antonio Moroni, M.D.

We would firstly like to thank Dr. Marsh for his overall positive remarks in the Commentary and Perspective that was published on the Journal's web site on our paper "Dynamic Hip Screw Compared with External Fixation for Treatment of Osteoporotic Pertrochanteric Fractures" We would, however, also like to draw Dr. Marsh's attention to a few points, which we feel deserve some clarification.

In contrast to what Dr. Marsh stated, we found that the Orthofix Pertrochanteric Fixator (OPF) provides better and different outcomes in femoral neck-shaft angle (FNSA) at 6 months as compared with the sliding hip screw group. Furthermore, fracture reduction was better maintained in the OPF group than in the SHS group, as shown by significantly lower fracture varusization at 6 months vs postop.

Concerning the possible increase in pain for the removal of the well- fixed HA-coated pins, this may be a problem for patients with good quality bone but, for the osteoporotic patient it is not. In a previous study of osteoporotic wrist fractures, we quantified pain during pin removal and no differences between standard and HA-coated pins were noted (1).

We completely agree that other implants such as intramedullary hip screw may be better alternatives than external fixation for treatment of unstable pertrochanteric fractures. However, particularly with these fractures, we are rather critical of the reported mechanical advantages of the sliding capabilities provided by implants such as the sliding hip screw and the intramedullary hip screw. The benefit provided by the ability of these implants to achieve fracture impaction at the fracture site can be overcome by the disadvantage of excessive sliding leading to limb shortening and medial displacement of the distal fracture fragment. If fracture impaction is excessive there is a lack of fracture reduction. We also believe that failure to restore the normal hip anatomy is a substantial disadvantage for elderly hip fracture patients.

Regarding the absence of pin-track complications, we believe that this result can also be reproduced by other surgeons because it does not depend on the surgeon skill or familiarity with the technique but on the excellent osteointegrative ability of the coated pins. This is confirmed by the similar consistent results reported by all the authors who have published on HA-coated pins (2-5).

Finally, concerning the shorter operative time found in the external fixation group, we agree that it may reflect the skill of the surgeon in performing external fixation techniques, however, we believe that as the learning curve plateau is reached, even inexperienced orthopaedic surgeons can achieve similar results. The shorter operative time results from the minimally-invasive approach of this technique which features the straightforward implantation of two pins of small diameter into the femoral head. With OPF there is no need of additional surgical steps such as predrilling, sizing and tapping which are used in the majority of the SHS and IMHS fixation techniques to implant one or even two lag screws of significant diameter into the femoral head.

References:

1. A Moroni, C. Faldini, S. Marchetti, M. Manca, V. Consoli, S. Giannini Improvement of the Bone-pin Interface Strength in Osteoporotic Bone with Use of Hydroxyapatite-coated Tapered External-Fixation Pins: A prospective randomized clinical study of wrist fractures J Bone Joint Surg Am. 2001 May;83-A(5):717-21.

2. Piza G, Caja VL, Gonzalez-Viejo MA, Navarro A Hydroxyapatite- coated external fixation pins. The effect on pin loosening and pin-track infection in leg lengthening for short stature. J Bone Joint Surg Br. 2004 Aug;86(6):892-7.

3. Pommer A, Muhr G, David AHydroxyapatite-coated Schanz pins in external fixators used for distraction osteogenesis: a randomized, controlled trial. J Bone Joint Surg Am. 2002 Jul;84-A(7):1162-6.

4. Caja VL, Piza G, Navarro A Hydroxyapatite coating of external fixation pins to decrease axial deformity during tibial lengthening for short stature. J Bone Joint Surg Am. 2003 Aug;85-A(8): 1527-31.

5. Magyar G, Toksvig-Larsen S, Moroni A Hydroxyapatite coating of threaded pins enhances fixation. J Bone Joint Surg Br. 1997 May;79(3):487-9.
"Dynamic Hip Screw Compared with External Fixation for Treatment of Osteoporotic Pertrochanteric Fra 16 June 2005
Previous Letter to the Editor Next Letter to the Editor Top
Rahij Anwar,
Registrar (Tr & Orth)
Maidstone Hospital, Maidstone, UK,
N. Gogi, S.A. Khan, A.A., and A.A. Iraqi

Send letter to journal:
Re: "Dynamic Hip Screw Compared with External Fixation for Treatment of Osteoporotic Pertrochanteric Fra

rahijanwar{at}aol.com Rahij Anwar, et al.

We wish to congratulate the authors for showing that external fixation can be considered as an option for the treatment of pertrochanteric fractures in the elderly patients with osteoporotic bones.

We carried out a very similar prospective observational study on fifty two elderly patients with pertrochanteric fractures. We used the standard pins (not hydroxyapatite coated) to externally fix these fractures. A sound and rigid fixation was achieved at the end of the procedure even in the osteoporotic bones. The average duration of hospital stay was 34.8 hours and average union time was 14 weeks. Harris Hip Score was used for evaluation. The following result was obtained:

Excellent: 15 patients

Good: 13

Fair: 9

Poor: 4

Our study showed that external fixation of trochanteric fractures was a simple, safe and economical procedure, which considerably shortened the duration of patients' stay in the hospital. However, pin track infection was seen in 15 (28.8%) patients. Although being superficial in most cases (11 patients), it responded well to local dressings and antibiotics, it was a constant worry both to the patient and the surgeon. Four (7.6%) patients had premature removal of fixator due to deep infection.

The authors state that there was no pin track complications in their series and they relate this to the use of hydroxyapatite-coated pins. Although the rigid construct using such pins does limit the pin movement in the bone, its value in preventing pin track infection is not clear. We believe that the irritation of the soft tissues by the pin at the pin-soft tissue interface is the main cause of local pin track inflammation/infection.

Other problems like knee stiffness, varus collapse, persistent thigh pain and poor patient satisfaction (because of the prominent frame) were also encountered.

We believe that external fixation for trochanteric fractures is only indicated in certain special situations like:

1. Unwell patients who can't tolerate long anesthetic.

2. Compound fractures.

3. Patients who refuse blood transfusions due to personal reasons.

4. Patients who can't afford the high cost of hospital stay and treatment by internal fixation.


Fig. 1 A unilateral frame is used to fix an intertrochanteric fracture.


Fig. 2 X-ray of the hip (AP view) showing a uniting intertrochanteric fracture eight weeks following external fixation.


Fig. 3 X-ray of the hip (AP view) of the same patient at 12 weeks post operatively showing union of the fracture. The external fixator has been removed.
External Fixation versus Dynamic Hip Screw for Pertrochanteric Fractures 8 June 2005
Next Letter to the Editor Top
MANOJ TODKAR,
ORTHOPAEDIC SURGEON
NUFFIELD ORTHOPAEDIC CENTRE, OXFORD

Send letter to journal:
Re: External Fixation versus Dynamic Hip Screw for Pertrochanteric Fractures

mtodkar{at}hotmail.com MANOJ TODKAR

To the Editor:

I read the article " Dynamic Hip Screw Compared with External Fixation for Treatment of Osteoporotic Pertrochanteric Fractures. A Prospective, Randomized Study" with great interest. I congratulate the authors for trying to find a solution for these common fractures in osteoporotic bones, a situation that presents a real challenge for fixation with conventional implants.

I am interested in knowing whether the time required for healing of the fractures treated by external fixation was significantly different from the fractures fixed with sliding hip screw. What was the stability at fracture site achieved after fixation ? Were the fractures fixed with external fixators less stable than sliding hip screws ?

It would also be very interesting to know the weight bearing status after fixation in group B. As you know, partial or non weight bearing is very difficult in this age group of patients.

Addlitionally, could the authors please tell us how long the fixators were kept on the patients? How did the patients manage with the bulky fixators on one side? In our experience, it is difficult for patients to manage with fixators as they have problems woth clothing, turning in bed and using support while mobilising.

Yours sincerely,

MANOJ TODKAR
Dr Moroni et al respond to Dr. Todkar 8 June 2005
Previous Letter to the Editor Next Letter to the Editor Top
Antonio Moroni,
Professor
Rizzoli Orthopaedic Institute, Bologna University,
Cesare Faldini, Francesco Pegreffi, Amy Hoang-Kim, Francesca Vannini, Sandro Giannini

Send letter to journal:
Re: Dr Moroni et al respond to Dr. Todkar

a.moroni{at}ior.it Antonio Moroni, et al.

Dear Dr. Todkar,

Thank you for your interest and your questions about our article: “Dynamic Hip Screw compared with External Fixation for Treatment of Osteoporotic Pertrochanteric Fractures.”

As you may know, in fracture treatment, assessing the time required for fracture healing is not a simple task and this assessment can be based on different types of analyses. In our study, fracture healing was defined radiographically by the presence of trabeculae bridging the fracture site or obvious periosteal callus within the fracture line. Based on this definition, no differences in the time required for fracture healing were found between the two groups.

In a clinical setting, stability at the fracture site cannot be measured biomechanically. However, upon clinical evaluation at the time of surgery, no differences in fixation stability were found between OPF and DHS. Long-term results (6 months) showed better stability with the OPF as demonstrated by a lower loss of fracture reduction. This was measured by comparing the femoral neck shaft angle at 6 months with the femoral neck shaft angle at post-op.

In response to your question regarding the weight-bearing status, there were no weight-bearing restrictions in either group. Patients were encouraged to resume their full weight-bearing capacity as they recovered from surgery. In this study, the amount of load which was actually placed by the patient on the treated limb was not measured quantitatively in the post-operative period.

In all the patients, fixators were worn for three months as reported in the study.

Certainly, the fixator was a cause of some discomfort. However, it was well- tolerated by patients and did not significantly affect diurnal activities such as bed rest and sitting. It should also be said that at 5 days after surgery, there was a significantly higher level of pain in patients treated with DHS than in patients treated with OPF.